Samsung Galaxy Ace Problem

[nelson2008]

I have just got a galaxy ace mobile and for some reason it keeps shutting down and restarting, i have taken the Sim card out and its fine but as soon as i put the Sim card back in it does it again,i took the phone into the car phone warehouse and they said it just needs to be restored to the factory settings which he did, but its doing the same again....... any answers out there? PS its on contract and i can send off for it to be repaired if there is a fault but am thinking its just a setting that can be set so it wont keep shutting down and re starting.

[237SJ]

I`ve got a Galaxy Ace and it`s never done anything like that. I reckon it`s faulty. Maybe it`s a battery connection or something.