I think the first thing to do is turn the phone off for more than 10 minutes and se if it being out of the loop fixes the issue. (10 minutes generally causes logins to time out.)

There was an issue years ago with apples mail offering that caused it to keep creating connections to an IMAP mail server until it was refused. This does make it get data faster. It also locks out other devices (even other apple ones) At the time there was no option in the apple mail product to actually limit the connections (Hence I suggest turning off the phone). Thunderbird will use up to 5 connections and the number used can be set in account settings >server settings > advanced.

Thanks but the issue is that I cannot get emails on my laptop to my main email account. I receive and send ok via the new phone so no problem there but it is really frustrating that the emails do not refresh on my laptop, I have had nothing since 06 January! Two of my email accounts (sales@ and accounts@) are sending and receiving ok but it is my main email account ( simon@ ) that is not working and I cannot fathom what to do. It keeps popping up a box that says "Enter your password for simon@lcm-clean.com on imap-mail.outlook.com", I have tried this and have then deleted the password (having read a previous contributor suggesting this helps) so now I have no password saved and no means to log-in. Please can someone advise next steps , I am not a tech expert so in simple steps and plain English please ;-))

I think I've sorted it!

Thanks for taking the time to read my post and offering help.

At least you know there are some of us out here that have absolutely no idea how computers, the internet, IT etc works and we stumble along hoping that it will all just work for us!