I have a group text chat with some people – call them Alice, Bob, and Carol – and it got misconfigured. For some reason, the message is going to Alice's work phone number instead of her cell phone number. Her work number is a landline, so naturally this doesn't work. But I can't figure out how to change it back. Some details:
If I create a new group message on my computer, with Alice-cell, Bob, and Carol, it just reuses the old group message and doesn't change the phone number.
I can message Alice-cell from my computer just fine on her own, or in other group chats. It's only this misconfigured one that's a problem.
On my iPhone, I have two group chats: Alice-work, Bob, and Carol; and Alice-cell, Bob, and Carol. They appear identical, because the contacts are the same, but only one works. Messages from both are combined into the one chat on my computer (with Alice-work, Bob, and Carol).
Alice has an Android phone, so solutions involving iMessage don't work here.
How can I fix this, so I can talk to Alice, Bob, and Carol all at once from my computer?