Why are only my messages in a group going through as text?

I have a iMessage group message with family. I have never had any issues with it. Suddenly, my messages are only going through as texts. Every other message and group is fine- they are still going as iMessage. It is only this one group message that sends my messages as text. Everyone else in the group seems to be ok except me. Anyone have any tips or input on this one?

Thanks