When I’m on my home network (no recent changes), frequently I can’t send a group message. It will give an error message to resend. Once I go to 4G, I’m fine.
Another layer of aggravation is that when I can send the group message, the responses come in through as a message I need to download on the individuals text threads. For example, I texted both my kids that my schedule changed. DD29 responded, but it didn’t come to the group message, it went to our thread, I have to download it, then it shows up in the group where I can open it and read it. When DD31 responds, it will usually be the same thing, but sometimes she shows up in the group and I don’t have to chase her response, download and find it again in the group. DD29 has an iPhone, DD31 has an android.