Bellow is shown the exact method to insert the unlock codes for LG GR500 Xenon

1- Power phone on with non-accepted SIM card
2- Select "Cancel" - phone displays "phone restriction code"
3- Dial unlock code, press OK
OR
1- Power phone on with accepted SIM card
2- Dial 2945#*9701#
3- Select SIM unlock
4- Dial unlock code press ok
5- Phone will then reboot
OR
1- Power phone on with accepted SIM card
2- Dial *#865625#
3- Press Yes to continue.
4- Dial unlock code
5- Dial unlock code AGAIN

And for Fido only

1- Power phone on with non-accepted SIM 

2- Select Unlock

3- Select UNLOCK USIM

4- Select SERVICE PROVIDER LOCK

5- Enter service provider code OR NSCK code

6- Press ok

Need an LG GR500 Xenon unlock code,can get it for less that 3$ :Lg unlock codes