Browser forcing weird email address and not actual email

RobertSparnaaij I'm having the same issue on my browser and I tried safari and chrome, both on my macbook - neither worked. The email address is still weird with a long string of characters. I also tried to discard the strange one but the problem remains. 

I'm having a separate issue with the outlook installed on the Macbook itself. It doesn't show the 'New Event' option in my calendar which is why I need to use the account from my browser to send meeting invites and Teams links but then the issue is the email address that goes out. I'm at my wits end and have been trying to troubleshoot all day!