I have a Samsung s5 and am in a group text with mostly iPhone users - high text usage; like 10 or 11 total people. It's worked perfect for the past 2 years. About 5 months ago, it stopped working properly.
Let's say 10 people are texting in that group string right now...everyone can see all the texts, but I'm only seeing texts from 2 of the people in the string. They can apparently see my texts. Any clue? This is maddening. I can say I used to have an iPhone years ago and my Appleid and iMessaging account have been killed.
I've tried the stock Samsung Messaging App. Google Messenger, Google Hangouts, etc. Same problem on all of them.