For a test, have them text the other user directly.
Bob
Trying to help a friend troubleshoot a bizarre issue. Both parties are in Canada with Bell for their carrier, one has a Samsung (believe Galaxy S4) and the other iPhone (believe 4G). The Samsung can receive texts from the iPhone and others, but when they try to reply to the iPhone specifically the iPhone never receives them. The Samsung user never had a mobile before this so I don't believe it could be the common iMessage issue, but I still had them explore this to ensure the iPhone is neither sending nor attempting to receive iMessages from the Samsung. Any thoughts as to what might be the issue?

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