Unable to receive group texts with Android device

I recently switched over to Att a few weeks and noticed I wasn't receiving texts from 2 people in my group text. One has an Android and one has an iPhone but they are both on T-Mobile. I have done everything. Checked all settings, reset network settings. Called Apple tech and they stated it was Att. Went into the store and was told there's nothing that can be done but to try a messaging app which is too much when I have always just used texting on my phone. There has got to be a solution to this because I know I can't be the only one dealing with this. It's 2020 technology should be advanced enough where it shouldn't matter what type of phone a person has in a group text, everyone should be able to receive the messages. Has anyone else experienced this and can you help?