Ferrari FF GEARBOX TEMP SENSOR FAIL

Need advice I had warning lights flash up so I took my FF to the dealer. Told me it was speed sensor.I agreed to have the work done, I put the car in after 4/5 weeks later I was told it was all fixed so I went to pick it up .No lights drove fine (I only done about 3 miles ).
I looked in the back and there was a Ferrari bolt on the floor and the rear floor mat had been pulled right out of the grommet and was on the back seat. I went back to dealer they told me it must have fallen out of the techs pocket and they fixed the mat. I then noticed and pointed out to the service guy that all of my leather had come away from the doors and rear panels, I asked had the car been left outside for 4/5 weeks in the Florida sun he told me yes. Told me they would try to fix the door cards.
I drove the car home next morning was struggling to start all warning lights came back on called dealer said I have a bad battery but I told him battery was only 2 months old. For the next week car was still struggling to start all lights on, i called dealer told me I had a dud battery or trickle charger was faulty. So I decided to change the battery as it was under warranty as I took the battery out I notice a Ferrari ok sticker from November 24 on the top.( I only put the new battery on in April 25) so i went and put another new battery on myself but I still had clutch overheat warning after driving for 15 mins.
Then i noticed 6 bolts were missing from the plastic that cover the engine bay. I took the car straight to the dealer they told me they had put my new battery on another car and put an old one on mine,they had no idea why the bolts were all missing.
I then booked the car in to have the door inserts fixed they told me they would put the missing bolts in and check for warning lights etc.
They had my car for 3/4 weeks again, I went to pick it up they said no codes drives fine all fixed. The leather was not attached had come off already repair was not a good repair.They told me they found some bolts around the shop and it was all done I opened the hood 2 bolts still missing said they would mail them to me (still waiting).
So I drove the car away 15 mins later clutch over heat warning on again. I booked the car back into the dealer told me it was maybe the PTU on the phone.I checked on the forum looked like the gearbox temp sender for most people, I told the service guy what I found asked him were all sensors replaced told me yes and if the sensor has failed its under warranty. So I had them pick the car up, they had it for 2 weeks again.
Emailed me today to tell me its the temp sensor and that it wasn't changed and its going to cost me another $13,425.00 to fix it.
I let him know I wasn't happy at all and I wanted to speak to management I'm now waiting for the call.

Sorry for the long story but I'm just looking for some advice, first and maybe the last Fcar I will own. Ive had it 5 years and loved it until this mess.