Unable to verify mail every time I am at a different location
Per Microsoft:

Microsoft prioritizes account security and works to prevent people from signing in without your permission. When we notice a sign-in attempt from a new location or device, we help protect the account by sending you an email message and an SMS alert. If your phone number or email changes, it's important to promptly update the security contact info on the Security basics page so we can work with you to keep your account secure and active.
If you sign in to your account while traveling or if you install a new app that signs in with your account, you may get an alert. We just need you to provide a security code so we know it was you, and that your account is safe.

I added the bold part.  It appears that MS notices the IP or access location is new or different than usual and requires the additional security login measures.
Catalina does not control your email access, it simply sends the credentials to the mail server.  It's possible that it takes time for MS's mail servers to validate your response to their security challenge.
I also have a Hotmail account and I use Spark as my email client on Catalina.  This happens to me when I travel but I find when I wait 10-15 min I can login again.  Strangely, this doesn't happen to my Yahoo or gMail accounts, only Hotmail (and Outlook but it's the same system).