Safari Version 15.0 (15612.1.29.41.4, 15612) will not load financial websites

This thread solved the issue for me on Catalina https://discussions.apple.com/thread/253165554

I couldn't update Safari, but the Safari reinstall fixed the problem.

There have recently been many similar reports of new problems with Safari. It seems that the recent Safari update has issues. Word has it that Apple knows about the problems and is working on a fix. I assume that it will be released fairly soon. In the meantime, use another browser such as Firefox or Chrome and they should work for you.

I do not claim to be an expert by any means. Seeing various issues posted on this forum for a long time is in itself revealing. Safari has had various issues for some users. Since the release of Safari #15.0 there has been an exponential increase in problems which did not exist prior to installing #15. When I said "word has it that...", I was referring to a posting by a user who was told this by Apple in a recent conversation. Was that true? I'm assuming it was. Logically, I can assume that Apple now knows they have some problems with Safari. Therefore, they would want to fix them. As to the suggestion to use another browser, you would be surprised that many users do not know to do that. Some are very proficient and it also amazes me that someone would spend thousands of dollars on a computer and then not attempt to learn how it works. But, many people do not. Working on this forum has taught me a lot. No one here has all the answers. We just try to help each other when we can.