Not getting Activation-Link emails.

I get OTHER Zoom emails just fine.  So they're not going to Spam. 

However, I am NOT receiving ACTIVATION-LINK Emails to classes for which I've registered.  I have a Zoom Basic Plan as I NEVER host sessions on my own.  I merely take OLLI classes through University of Denver and lately can NOT get Activation-Link Emails from Zoom. I used to get them just fine.  I've also already worked with a Tech Guru for DU's OLLI classes, and he can't figure out why I'm having this trouble.  I "CAN'T" get more Zoom Support Help unless I upgrade my Basic Plan. AARGH!

Any suggestions welcome.