Not getting invite link each time

[COEGF]

A participant just got a new modem. Now they don't receive the invite link each time, just some of them. Is there any way to help them on my end?

[mgstark]

@COEGF Hi there, it sounds like it might be related to the email blocking some of the messages. Please ask them to check the trash folder or if they can try another email address. The new modem is unlikely be related to the issue.

[Bloomerl]

Except the non-response is to several totally different organizations so even if one were blocking, that doesn't explain why they're all blocking.