my x3 has developed an intermittant problem and was hoping someone has had similar and can point me in correct direction for repair.

when i try to lock the car the key fob would not work tried loads of times but nothing happened,tried using the spare key but that did not make any difference.
then after an hour or so both fobs started working correctly,i have had the fault happen a few times even when trying to unlock aswell.when it failed to unlock i opened with the key and started up but alarm siren continued to sound for about 5 minutes of driving,i thought turning ignition on was supposed to reset the alarm?
once home the key fobs locked and unlocked as normal.

has anyone else experienced a similar problem if so what was the fix?

thanks