I did a job for a SubContractor on NAFB in Las Vegas Nv, I never signed a contract because I took over the job from a previous contractor who couldn't finish the job and was told that if I signed a contract that I would be responsible for all the previous contractors work, so I just got change orders, so the paid when paid should not pertain to me. They are saying that because I signed a contract for another job I had with them that I had to wait for payment because that was a master contract. Is this true ?