I just upgraded LG-D850 (AT&T) from Kitkat 4.4.4 ver to Lollipop V20A, kdz file using lg flash tool (downloaded from lg-phone-firmware site)
After upgrade, it asking me for Enter PIN/Password to decrypt 30/30 attempts remaining
and it also shows popup which says current version is not available for user can't find matched cust fot nt-code mcc/mnc[310410], subset[ff]

I dont know what does it means and how to solve this issue ?