E5575s-210 impossible to unlock

[smartdoc]

Hello, i've this modem and i've buy some credits to unlock it but it can't be unlocked. I cant also add APN for other sim. Can you help me?

Thanks all

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DC - Unlocker 2 Client 1.00.1429

Detecting modem :

selection :
manufacturer - Huawei modems
model - Auto detect (recommended)

Found Applications port COM77

Found modem : E5575s-210
Model : Huawei AuthVer 4 modem (New)
IMEI : 866887022754132
Serial NR. : E9RDW16504000665
Firmware : 21.317.01.01.12
Dashboard version : WEBUI_17.100.06.16.12_MRE5
Web UI version : WEBUI_17.100.06.16.12_MRE5
SIM Lock status : unlocked
Wrong codes entered : 8 (unlock attempts left : 2)

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Unlocking, please wait ...

AT command error

Error code 37

unlock failed !

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[Valdemaras]

Device's that run 2x.3xx.... firmwares are not supported for unlock sadly.

[smartdoc]

Device's that run 2x.3xx.... firmwares are not supported for unlock sadly.

is not possible to downgrade?

[Valdemaras]

is not possible to downgrade?

Most likely no.