Just go into options and set the screen lock timer to a longer time, not sure why you need your cell phone company to do this for you unless you tried and it's not helping. This is also not a direct connection to any carrier or support site, it's a general user to user general support forum. Any issues you have with your cell carrier, you need to contact them through their support site/phone number.
They would not have setup a locking password on your phone, you need to do that yourself.