Please explain the problem in detail. What happens? What is/are the exact error message(s) ?

Make sure you are not blocking content.

Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop

Same problem in Safe Mode. Trying to access credit card account I get through the first layer of security then have to generate a code using the banks app. I input this into the second security layer and it doesn't get accepted. I clear cookies and try again but the same happens.

Remove History For One Site {web link}

Open the History Manager <Control> (Mac=<Command>) <Shift> H. In the search bar, enter the name of the site. Right-click on one of the listings and select Forget About This Site. This should remove all information, including any site settings

No history, I have all cookies etc dleted when Firefox closes. However, I have the trackers blocking set to 'strict'. Could this be the problem, if so how do I sort it? Apologies for the delay in my replies, I'm the other side of the Atlantic.

. . . I have the trackers blocking set to 'strict'.

As a test, turn it off.

That works!

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