unlock code ford fiesta 54 reg?

my girlfriend has just had her starter motor replaced and as this ment the battery was disconnected it has wiped the code on the radio. she has only had the car 6 months and when i`ve checked the book for her code it`s not there spoke to arnold clarke and they don`t have record can any one help
her serial number is m094871
radio model is 42500 rdse

thanks in advance

Penno