@Poorshad
There's a couple of types of locks on a Samsung Phone.
The first is the Region Lock you mention.
To remove that a culmitive call of 10 minutes needs to be made in the country of origin using a local sim card and the call is made to a local number.
Another option is to contact the Samsung Support Department for that country and ask them to remotely remove the Region Lock.
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The 2nd is some phones are locked to a particular network if the phone was supplied by a mobile network as part of a mobile phone contract.
The unlock to all networks usually is carried out by the network that it's locked to.
They will have their own set process and a criteria to meet before unlocking.
If Samsung supplied the phone directly then it should already be unlocked to all network's.
Daily Driver > Samsung Galaxy s²⁵ Ultra 512Gb ~ Titanium Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
