Messages app keeps saying "You left the conversation" and kicking me out of a group chat

I have an iPhone 11 and a Macbook Air running the latest software. I am in a text thread with two other iPhone users. I keep getting kicked out of the text thread with a message saying "You left the conversation" but I didn't. After this happens, the group chat doesn't appear in my list of conversations. If I want to send a message to them in the Messages app on my laptop, I create a new message and add both of their names in the "To:" field, and the conversation reappears. However, if I type a new message to them, it just disappears and doesn't actually send (because I "left the conversation"). The only way I can re-enter the conversation is by repeating this process on my phone. If I create a new message to both of them and send it on my phone, it will go through, and it puts me back in the conversation so that I can send messages from my computer. But after some time, I get kicked out again and have to go through the same process over and over and again.