Unable to access bank webpage
Over the last two years my bank, FirstHorizon of TN, has made changes to its online web platform. In four instances, right after the change I have been unable to access my account page. I complain and their IT department fixes it somehow. Two weeks ago the problem reoccurred and I called First Horizon. A ticket was created in their IT department. Last Sunday and Monday, the problem disappeared and I was able to access my account. Then on Tuesday the problem came back. Now the IT department says the problem is with my system. I use a late 2015 iMac with MacOS Monterey 12.7.6 and Safari 17.6 and have been for years. I also have a mac-Mini M4 with Safari 18.6. The problem occurs with both computers and both versions of Safari.
When trying to log on to the bank's webpage the bank's system accepts my user name and password, navigates through their security screen, and then begins to load the bank account page but hangs up without displaying any of the account information. Does anyone have any ideas about what the problem could be because the bank has closed out the ticket and left me high and dry.
iMac 27″, macOS 12.7