Transfer daughter to another family in icloud family sharing

My 12 year old daughter has been in my husband's icloud family share plan, however I want to transfer her to mine. I have read and followed instructions online but none of them have worked. When I send the invitation to join my "family" it says she is already in a family and can only be in one family at a time. When I follow the instructions to transfer her, that does not work either. On my husband's phone in settings, the option to "stop using family sharing" is not a working button/link and says beneath it that I must first transfer my daughter to another family before stopping. It just seems as though every instruction to do this is not working when I actually try to do it. Any ideas? Thank you!