Kessy dry, but vehicle can not start, key is not recognized

Moin Moin, I know the subject is up.. but I found nothing in the constellation. The Phaeton stood with me for a long time rum, and I noticed already when I put the two weeks ago into operation, how he had difficulty to recognize my key (thought key battery is dead, was replaced earlier). Now I wanted to go to the car today. AGM just hung on the charger, installed it and wanted to unlock the car. Over the remote control nothing went. The alarm So the driver’s door opened, alarm lights remained on. Put in and the car started shouting. So I “plugged off” the wire of the siren with force and both batteries also to open the footroom without the DWA bothering me. Here I noticed; the Kessy is Furztrocken!! I then called in Lüdinghausen, they could tell me ad hoc but nothing. Maybe read out. When the batteries were still in, my key was held (must have called in Lüdinghausen, but they could not tell me anything. Now I don’t know if the DWA horn is really paralyzed now by just plugging it off – it went off two more times afterwards, then it was off. I don’t want to connect the batteries to disturb half the neighborhood when reading the kessys and be allowed to deal with the police. Furthermore, I am about to expand and investigate the kessy, because the keyless anyway never klakla ppt. So I suspect creeping corrosion in kessy, which has now finally taken it off. Is one even able to read the car without ignition? The car steals me 100% again the key. Anyone advice how to continue here? Currently the car stands on a main road in a quiet place at a 10+° elevation. Towing is also stupid.. Best regards and in advance thank you for any help. Your Don