RENAULT-forum

I am looking for an automatic gearbox sensor for my Twingo from 2000.
It still only runs in emergency mode. Warning lamp indicates after reading at the dealer: Error message 6G circuit TT sensor output gearbox (automatic). Part number 7701201830.
Part in nowhere to be found and I am now desperate for the search. My deceased wife bought the twingo new and I would like to keep driving instead of taking the car to the scrap yard. I have already spent a lot on it and otherwise it is in good condition.
Who, oh, who can help me to find this part anyway.
Thanks in advance!