Ford Fiesta won't start

Hi.

Early December my car was experiencing problems changing from 2nd to third gear and then stopped completely. It was towed to an electrics guy who after a few days managed to take apart the gear box and fix the problem (actuator). All has been great since. Tonight I was very low on petrol but late so decided to fill up on way back. I drove to my daughters school, went in to get her and upon returning the car would not start and the gear display kept reading 0 regardless what I did. I left in 10 mins and it started and drove home fine, I also stopped for petrol and car restarted after this also. I called the mechanic and said do you think it may be the same problem but he said no way he is positive he resolved that issue. He is happy to take the car back but I have no other transport here and no one to help out. Just wondering if anyone has any ideas?

thanks