We can send emails between every one INSIDE the domain but not outside it

Well, the title. Strangers do not receive our e-mails and I’m not certain but I think we do not receive them either. I already routed them and between all of us it works with the “contraptions”: Ex. “[email protected]” sends an email to “[email protected]” and it goes through perfectly well. But if “[email protected]” sends an email to “[email protected]” the email doesn’t go through.

Any help?

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