Cub Cadet review: Cannot get assistance for company

I purchased an LT2 Enduro riding lawn mower with Cub Cadet's EFI engine from an authorized dealer in 2020. This upscale mower performed perfectly for 3 years with only routine maintenance. Last year, the mower developed a problem early in the mowing season I returned it to the dealer for repair. The engine lost power and "backfired" continuously. According to the dealer, they could not get the necessary part from Cub Cadet in a timely basis. I finally found the factory part from another source and purchased it. The dealer installed the part and the mower ran fine. I brought the mower home and as I was unloading it off of the trailer, the same problem occurred. I loaded the mower back on the trailer and returned it to the dealer. I did not get the mower back until the end of the season. I attempted to mow for the first time this year but after a couple of hours, the problem has reappeared. I tried to call the company but have been kept on "hold" with no real person answering and I have tried to use their chat function but I am redirected to the lawn mower identification sales page.