Received call from XXXX advising they were Calvary Portfolio calling on a personal matter. I researched and found they were debt collectors, I called back. They said it was a personal matter when I asked if they were debt collectors. I advised that pursuant to the debt collection laws I requested that contact in future be in writing, they again advised was personal matter. I spoke with agent XXXX at ext XXXX and then the floor supervisor XXXX, that was the names they provided. They have been put on notice and still fought me on calling back to discuss the matter. I feel they are using " personal matter '' as a way of hiding their true nature and an attempt to get around the fair debt collection act laws.