Hello MaRoRQ,
Welcome to the Microsoft Community. Thanks for supporting Microsoft products.
Recently, many users have reported in the Community that they are unable to receive a verification code when logging into their Microsoft account, and we understand the inconvenience of this issue. This appears to be a temporary anomaly in Microsoft's authentication system. While we wait for it to be fixed by Microsoft, it may be worth trying the following steps to see if they help with a successful login.
Some users in the community have been able to add authentication methods that use the authenticator so that they can eventually successfully sign in to their Microsoft account.
Microsoft is trying to send me a verification code so I can sign in to - Microsoft Community

How to use two-step verification with your Microsoft account - Microsoft Support
Download Microsoft Authenticator - Microsoft Support
I hope this is useful and if you have any questions please let me know.
Best regards,
Ian - MSFT | Microsoft Community Support Specialist