Not sure how long this has been going on, but my iPhone 4s often does not receive group MMS messages.
I've noticed that if someone sends a group text that is to all iMessage users I receive it just fine. If it is a mix of iMessage/regular SMS users that's when I don't receive it.
Also have been missing messages when someone group texts from an android device.
I've done a hard reset and still having this issue.
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