I have just updated as soon as i did i went to settings under wifi it said carrier with att beside it i click it it starts loading then says error now its not there any hints am i the only 1?
Your not the only one. All UK users have this with most phones. It is used to try to change the carrier when it can't find the normal one due to bad signal.
Most of the time it doesn't work/not needed - don't worry.