Hi, ive got a 2005 116i sport, when i put the key thing into the slot the dash lights up as normal but when i push the start stop button the car wont start, it does start sometimes but the problem is getting worse. i sat tonight for 20 minutes before i could get it to go. if someone could help that would be great thanks
ive tried the spare key and it does the same with it, i dont think its the battery because the car does start after i pull the key in and out 10-20 times.

sounds like to me an immobiliser problem if the car is still in warrenty it will be free but shouldnt cost much to have sorted out at a dealer such as greens etc, however it may cost a lot to fix also it could just be a key fob problem wich if the key is not censored near the ignition the car wont start like the AA vans, this problem should cost between 15 and £50.00 best bets take it to a dealer for a diagnostic check up,
Hope This helps :)