Yup change your phone number. Otherwise, the debt collectors can only be called off by the companies who instructed them, so all you can do otherwise is to ask them who they are calling on behalf of, and write a stiff letter to those companies. Have you done a credit check (experian etc) on yourselves since you moved? that would throw up bad credit for other people living at your address, you can then ask experian to correct the record. You don't want this problem affecting your future creditworthiness.