Sign-in requests are not received. Authenticator asks me to verify, no request received

Question

I am trying to use Authenticator on my Android phone but no sign-in requests are received. I have uninstalled Authenticator and re-installed it. When trying to log in, it asks me to approve the request on my Authenticator! I tried the code via email method but no code is ever received.

I have been trying this for three days now. The online "sign-in helper" is no use. It fonds no issue with my email. I can't get webchat support - all it does is raise a support call back request and no-one ever calls back. The support phone numbers are nothing of the kind - they just send a link to the same unhelpful support page where I started.

My email address and Microsoft account are fine. Outlook on the desktop and Android phone works fine. But I can no longer access Microsoft forms to see the results of a form I created and published last week. When I try to access it, it wants me to approve a sign-in request on my Outlook app - nothing is ever received. I try with Authenticator, no approval request ever received.

The phone I am using is my old Android on which Authenticator used to work normally. My new Android phone also used to run Authenticator normally. I don't have access to that as it has been factory reset to send away for repair.