I'm also having this problem. I have a Samsung Galaxy and sent a group message to 2 other people who have iPhones. They are also Verizon customers but not on my account. Message shows to be from [removed].... which shows to be a Mexico number.
When I look at the group on my phone, that number is not there but when they get the text it shows to be a group of 4 people.... me, the 2 people I texted and someone with that 588 number. This is a family group and I chose to name it "family" does that somehow cause this?
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