2018-2020 AT&T currently unsupported.
AT&T LG Phoenix 3 (M150) issue:
Important: There are a lot of the new LG Phoenix 3 M150 devices from AT&T that are currently sold with firmware issue and they can not be unlocked!!! Their lock counter is frozen and rejects every unlock try as "SIM Network unlock request unsuccessful_001" even if code is correct!
Please, if you have new LG Phoenix 3 M150 from AT&T, check if the lock counter is active by dialing a random code. If devices changes the number of tries left in the lock counter(2/10) it can be unlocked. If tries stay always 1/10 than device can not be unlocked.
Check before processing AT&T LG Phoenix 3 (M150) devices as there will be NO REFUND for such issues!!!
Please make sure your LG model can be unlocked with Network Unlock code before making a purchase.
(No Refund if your phone has no method to enter code) check before ordering on Google.
You would need to downgrade to firmware version A, B, C, D, E version
Newer firmware version above I,L,M,N