Email problems

Yesterday I lost all access to my virgin media email accounts on my iphone (3 separate virgin media addresses). Every time I open my mail app on my iphone I get messages for all 3 accounts saying Password Incorrect - Enter the password for the IMAP account "XXXX". I tried deleting one and opening as a new one but unable to do that keeps saying username and/or password incorrect. I have changed my password for my virgin media log on but it has made no difference.

I can access the accounts on line through a web browser

I read something about having to set up an app password and to do this you sign in to your virgin media account which I can do but the app password is set up through the 'manage my products' box. However, whenever I click on that box it says 'something went wrong - try again'. I get the same problem of not being able to get through to manage my product regardless of what browser I use, tried chrome, edge safari and in the my virgin media app - all the same!