On what device and how are you accessing your email. Is it by using a web browser or an email client/app.
If you are using your email via an email client/app, in the settings make sure you have ticked the box "remember password".
It happens on my laptop via Outlook. It's only started happening in the last few weeks since BT sent an email about new Emails service.
It doesn't happen on my phone.
I have clicked the link and added the account, and then sent myself an email and it requested a password, so that didn't work.
Do you know where the box is to check to remember my password?
I realised I didn't need to set up another account as it was already there. I checked the IMAP settings etc and they were correct. I guess I need to delete that additional one now though not sure which one it is. I guess it might be the one that says (1) after it?
I found the password tickbox as it's there when it requests your password, so I think that was all I needed to do. Have sent test email and it didn't ask for password so that was all that was required.