Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Glad it's not just me and thanks for replying.. I got a standard response for MS:
Hi Alex,
Thanks for contacting Microsoft technical support about your issue.
Helpful resources for you:
How to help keep your Microsoft account safe and secure - Microsoft Support
5 ways to protect your Microsoft account | Microsoft Security Blog
I just went in and changed my password and it seems to have stopped for now. MS do not appear to want to investigate the source - if they did, perhaps they could find out who is requesting these codes under our name.
All rather worrying and disconcerting.