VM do not deliberately block e-mails from any domains unless they appear to be spam or have the characteristics of spam. Usually this results from badly configured systems at the senders end.
The best thing you can do at this stage is to ask the school to look at their e-mail logs and see what happened to the mail they send to you. The logs will contain information about the messages sent back by the VM mail servers.
You can then post the logs here (edit so that your e-mail address is not fully identifiable, leave the domain name in full) and we can advise further.
It would also be helpful now if you could post the full domain name of the school - you put xxs in where the name was. We (and any one can do this) can then run a check on how their mail server is configured (SPF record).
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