Business ProfileforDolan Dodge Ram Fiat

My car's driver side window regulator got broken. Left the car on 4/28/2022. Was told that I'll get contacted the next day with an estimate for the repairs. Indeed, the estimate was about $450, which we thought is too much, so we declined. Went to the dealership to pick up the car, got an invoice for $180 (that's the hourly rate!!!) for "diagnostics". I never signed anything to that effect. Moreover, the invoice states that a technician removed the door panel to diagnose the problem, and also indicated that the insulation panel "was breaking apart". That makes me believe that they never did anything to the car, as the insulation panel was intact when I removed the door panel myself (a 15 minutes job for a non professional mechanic as myself!). I am attaching a photo of the insulation panel, I'll leave it to anyone's judgement if that's "falling apart". I want to get a refund for the full amount of the invoice, unless I am shown a document with my signature where I agreed to diagnostic fee. Note: I paid the invoice at the time, wanting to cut down my losses and not argue with the outrageous "diagnostic" fee, but I got really mad when I started to suspect that absolutely no work was performed on the car.