SM-A510M FRP problem

hello there!, im trying to remove FRP from sm-a510m, if i want to do with boot.img, i got the phone into a bootloop, also if i do via the new update (Factory Services), im getting :

Octoplus/Octopus Samsung Factory Services v.2.4.5
———————————————————————–
Selected interface: USB
Searching for device. Please wait…
Waiting for device…
Found device on COM198
Reading info…
Detected device model: SM-A510M
HW Version: SM-A510MZKMTTT
PDA version: A510MUBU3BPJ1
CSC version: A510MUUB3BPJ1
CP version: A510MUBU3BPI3
Device SN: R28H33ASZ4E
Device IMEI: 358519-07xxxxxxxxxxx
FRP/Reactivation: TRIGGERED
Connecting to server..OK
Username:
Authorization..
Login error: Wrong username!