In old nokia phone u get contact service when u downgrade phone version
As security file damaged rpl etc, but in recent time u get contact service after flashing lower or higher version
But not the version is the problem but manfucturer


After nokia fall in buisness microsft bought it and issued new nokia such as nokia 105 on phone cover nokia name
And nokia logo on sofware but on sticker microsoft after 2016 nokia bought buy HMD global


You will read HMD global on phone sticker under battery
So if flash Nokia by Microsoft with hmd global version u will get contact service and vice virsa


Ok first before u flash phone do this
Open Best
Go mtk section
Service tab
Tick rpl only and press flash then connect phone


Now from log u can check version





Just flash phone with same version in log
But if u got phone with contcat service issue
Do same method
Read flash with rpl only ticked





If in log
Control Block Validation (Security Test) :
CBR is Ok, match with BB SN. Phone Security is Alive
Mobile Info


Just flash phone with same version in log or with lower if phone by microsoft
or higher if by HMD global




But if u get this in log after reading rpl
CBR Info is wrong! CBR SN not match with BB SN!
If backup not done - phone just a brick
Then no solution