The bank was using an incorrect model as it assessed its own risks amid rising interest rates, and spent much of 2022 under a supervisory review.

Silicon Valley Bank’s risky practices were on the Federal Reserve’s radar for more than a year — an awareness that proved insufficient to stop the bank’s demise.

The Fed repeatedly warned the bank that it had problems, according to a person familiar with the matter.

In 2021, a Fed review of the growing bank found serious weaknesses in how it was handling key risks. Supervisors at the Federal Reserve Bank of San Francisco, which oversaw Silicon Valley Bank, issued six citations. Those warnings, known as “matters requiring attention” and “matters requiring immediate attention,” flagged that the firm was doing a bad job of ensuring that it would have enough easy-to-tap cash on hand in the event of trouble.

But the bank did not fix its vulnerabilities. By July 2022, Silicon Valley Bank was in a full supervisory review — getting a more careful look — and was ultimately rated deficient for governance and controls. It was placed under a set of restrictions that prevented it from growing through acquisitions. Last autumn, staff members from the San Francisco Fed met with senior leaders at the firm to talk about their ability to gain access to enough cash in a crisis and possible exposure to losses as interest rates rose.

It became clear to the Fed that the firm was using bad models to determine how its business would fare as the central bank raised rates: Its leaders were assuming that higher interest revenue would substantially help their financial situation as rates went up, but that was out of step with reality.

By early 2023, Silicon Valley Bank was in what the Fed calls a “horizontal review,” an assessment meant to gauge the strength of risk management. That checkup identified additional deficiencies — but at that point, the bank’s days were numbered. In early March, it faced a run and failed, sending shock-waves across the broader American banking system that ultimately led to a sweeping government intervention meant to prevent panic from spreading. On Sunday, Credit Suisse, which was caught up in the panic that followed Silicon Valley Bank’s demise, was taken over by UBS in a hastily arranged deal put together by the Swiss government.

Major questions have been raised about why regulators failed to spot problems and take action early enough to prevent Silicon Valley Bank’s March 10 downfall. Many of the issues that contributed to its collapse seem obvious in hindsight: Measuring by value, about 97 percent of its deposits were uninsured by the federal government, which made customers more likely to run at the first sign of trouble. Many of the bank’s depositors were in the technology sector, which has recently hit tough times as higher interest rates have weighed on business.

And Silicon Valley Bank also held a lot of long-term debt that had declined in market value as the Fed raised interest rates to fight inflation. As a result, it faced huge losses when it had to sell those securities to raise cash to meet a wave of withdrawals from customers.

The Fed has initiated an investigation into what went wrong with the bank’s oversight, headed by Michael S. Barr, the Fed’s vice chair for supervision. The inquiry’s results are expected to be publicly released by May 1. Lawmakers are also digging into what went awry. The House Financial Services Committee has scheduled a hearing on recent bank collapses for March 29.

The picture that is emerging is one of a bank whose leaders failed to plan for a realistic future and neglected looming financial and operational problems, even as they were raised by Fed supervisors. For instance, according to a person familiar with the matter, executives at the firm were told of cybersecurity problems both by internal employees and by the Fed — but ignored the concerns.

The Federal Deposit Insurance Corporation, which has taken control of the firm, did not comment on its behalf.

Still, the extent of known issues at the bank raises questions about whether Fed bank examiners or the Fed’s Board of Governors in Washington could have done more to force the institution to address weaknesses. Whatever intervention was staged was too little to save the bank, but why remains to be seen.

“It’s a failure of supervision,” said Peter Conti-Brown, an expert in financial regulation and a Fed historian at the University of Pennsylvania. “The thing we don’t know is if it was a failure of supervisors.”

Mr. Barr’s review of the Silicon Valley Bank collapse will focus on a few key questions, including why the problems identified by the Fed did not stop after the central bank issued its first set of matters requiring attention. The existence of those initial warnings was reported earlier by Bloomberg. It will also look at whether supervisors believed they had authority to escalate the issue, and if they raised the problems to the level of the Federal Reserve Board.

The Fed’s report is expected to disclose information about Silicon Valley Bank that is usually kept private as part of the confidential bank oversight process. It will also include any recommendations for regulatory and supervisory fixes.

The bank’s downfall and the chain reaction it set off is also likely to result in a broader push for stricter bank oversight. Mr. Barr was already performing a “holistic review” of Fed regulation, and the fact that a bank that was large but not enormous could create so many problems in the financial system is likely to inform the results.

Typically, banks with fewer than $250 billion in assets are excluded from the most onerous parts of bank oversight — and that has been even more true since a “tailoring” law that passed in 2018 during the Trump administration and was put in place by the Fed in 2019. Those changes left smaller banks with less stringent rules.

Silicon Valley Bank was still below that threshold, and its collapse underlined that even banks that are not large enough to be deemed globally systemic can cause sweeping problems in the American banking system.

As a result, Fed officials could consider tighter rules for those big, but not huge, banks. Among them: Officials could ask whether banks with $100 billion to $250 billion in assets should have to hold more capital when the market price of their bond holdings drops — an “unrealized loss.” Such a tweak would most likely require a phase-in period, since it would be a substantial change.

But as the Fed works to complete its review of what went wrong at Silicon Valley Bank and come up with next steps, it is facing intense political blowback for failing to arrest the problems.

Some of the concerns center on the fact that the bank’s chief executive, Greg Becker, sat on the Federal Reserve Bank of San Francisco’s board of directors until March 10. While board members do not play a role in bank supervision, the optics of the situation are bad.

“One of the most absurd aspects of the Silicon Valley bank failure is that its CEO was a director of the same body in charge of regulating it,” Senator Bernie Sanders, a Vermont independent, wrote on Twitter on Saturday, announcing that he would be “introducing a bill to end this conflict of interest by banning big bank CEOs from serving on Fed boards.”

Other worries center on whether Jerome H. Powell, the Fed chair, allowed too much deregulation during the Trump administration. Randal K. Quarles, who was the Fed’s vice chair for supervision from 2017 to 2021, carried out a 2018 regulatory rollback law in an expansive way that some onlookers at the time warned would weaken the banking system.

Mr. Powell typically defers to the Fed’s supervisory vice chair on regulatory matters, and he did not vote against those changes. Lael Brainard, then a Fed governor and now a top White House economic adviser, did vote against some of the tweaks — and flagged them as potentially dangerous in dissenting statements.

“The crisis demonstrated clearly that the distress of even noncomplex large banking organizations generally manifests first in liquidity stress and quickly transmits contagion through the financial system,” she warned.

Senator Elizabeth Warren, Democrat of Massachusetts, has asked for an independent review of what happened at Silicon Valley Bank and has urged that Mr. Powell not be involved in that effort. He “bears direct responsibility for — and has a long record of failure involving” bank regulation, she wrote in a letter on Sunday.