General Motors review: gm radio diagnostics check

On Friday, 10/25/19, I took my 2007 GM Yukon in because when my husband changed out my battery, my radio stopped working. I took my vehicle in for diagnostics and I was told that the radio was bad and I needed a new radio for close to $800. I told them I would have to decide on that. I asked if there were any read out codes or anything on the diagnostics and was told I just needed a new radio and that it must have just been coincidental that all this occurred at the same time.
Today, Monday, 10/28/19, I was backing in my carport and my back up bell began to ring and I looked down and the clock was up on my radio, I turned it on and it works. The CD and DVD also works. Everything seems to be back to normal.
I called back to the dealer and explained this and ask if my $52.00 could be reimbursed because the diagnostics was incorrect and was told no that the radio could go back out at some point and the technician, Thomas, never has diagnostic errors. The person I spoke with, Tristan, was not in the business of satisfying a customer and this GM Lifetime customer was not happy with the answer. My family and I have always driven GM vehicles and will continue; however, I felt the need to report this issue.

I have attached a copy of my receipt.
Thank you for your assistance in this matter.

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