Group text hasnt been working for 5 weeks.

My group text on my samsung galaxy s7 edge hasnt been working for a long time now. Whenever i send messages, they turn orange and fail. I also cant see thumbnails for sent images in group text, but I can load them by clicking on them. I have already called customer support twice, and their solutions fix the problem once or twice and then stop working completely. I've reset the messages app and cleared its data 15 times now at least. How can this be fixed? The group chats have stayed well under the 10 person limit.