BT/computer email problems

[Headstone]

Good evening computer types

We have a BT address as our main email, and have done for many years quite successfully but we now but we have a problem which was first apparent on my wife's lap top but is now affecting my computer.

I first noticed something odd over the last few weeks when using the laptop that when typing or editing an email I would occasionally get a message in the centre of the screen that said "System Busy Please Wait" which eventually cleared and I was able to carry on.

Now however I can open the internet using Google Chrome and the BT Homepage comes up fine but when I click on email I get a blank page, in the top left corner it says Email Login Page and in the centre of the page is a small clock kind of display going round and round and nothing happens. I tried looking at my emails on Firefox which worked a few times but now has the same problem but it does work using Microsoft Edge - at the moment
We can pick up emails on my wife's phone OK.

All other parts of the internet, BBC, pprune and newspapers seem to be OK and my own GMAIL is working fine.

Any ideas?

Thanks
H