I think this is the same as the IP angle others have pointed out. If there was no contract (written or verbal), then no IP transfer took place and OP still owns

I think this is the same as the IP angle others have pointed out. If there was no contract (written or verbal), then no IP transfer took place and OP still owns all the work they did. Contracts also can't transfer value without proper consideration. So even if there was some sort of contract, it's not valid until OP receives compensation for the IP.