The domain [xyz] is not recognized
This generally means that we haven't added your institution to Hold yet and therefore you will not be able to verify your account at this point.
If we've added your institution and you received this message, then the error is most likely on our side. Please let us know and we make sure that you will be able to verify your account.
[xyz] is not a valid email address
There might simply be a typo in your email.