How bizarre! And hey, we want to make sure you stay in the loop with your friends via group texting so we'll get you up and running again. First, when sending the message, do you receive any error messages? And are you able to select all of the parties you want to send the message to without issue? Also, do you have any issues with data? Or does this happen every single time? For now, please go to settings > messages > enable "Group Messaging". Then remove/reinsert the SIM for a network refresh and try again.
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