Frustrating email issue

Not strictly RW related, but I didn’t know who else to ask.

I keep getting blocked by my ISP’s firewall due to unsuccessful log in attempts from my emails. I have been working with them to resolve the issue, and we seem to have isolated the issue to one machine - my main work iMac.

I have uninstalled any email accounts hosted with them from all of my devices, but they say that they are still getting the unsuccessful log in attempts.

I have run two virus scans (using Malware Bytes and Bitdefender) and they both say my iMac is clean.

Everything was working fine on Monday and the only changes made were to update my website at www.thebuskers.co.uk. This site has a foundation form linking to one of the email addresses. Could this cause an issue?

I haven’t got an issue with the hosting company - they have been pretty good and I’ve been with them a while.

Any suggestions would be much appreciated.

Thanks in advance.