Carshield Did not uphold warranty contract Internet

I put the Carshield "warranty" on my 2013 GMC Acadia as soon as I bought it. Paid my monthly premium on time every month. Started to hear a knock in the engine so I took the vehicle in. Was told by a mechanic that it was the oil pump that needed replaced. For nearly a month I could not get a hold of the Carshield agent that was in charge of my account. For nearly 6 months they disputed my claim even though the part that caused the damaged was in their fine print as being covered. They finally approved replacing the engine. They found the engine and all the parts needed to replace engine. Mechanic replaced the engine. This is after 8 months almost. Luckily the dealership replacing the engine gave us a really good deal on a loaner car because the Acadia was the only car we had. Once the engine was replaced and ready to go, Carshield then claims the mechanic did not use approved parts. Mind you, HE USED THE PARTS THEY SENT!!! It cost me over $2K out of pocket to get my car back 9 MONTHS AFTER FILING THE CLAIM.