@simong, I think there should be carrier billing for Windows Phone 10 as well.
Why carrier billing is not available even after Digi SIM is inserted?
You might need to upgrade the device software to the latest software version (at least GDR2). Click on Settings – Phone Update – Menu – Check for Updates.
Reboot the device, Digi SIM card must be in the device during reboot.
Automatic discovery can take sometimes several days and it requires AC wall charger or wireless charger, not USB charger, to be used.
Windows ID and device country setting should be set to Malaysia.
If Microsoft Store has been used first time in other country, it can be locked there and require phone reset to change to Malaysia.
The phone needs a data connection during out-of-the-box experience. If it is roaming and cannot connect to the network, discovery will not trigger until it’s plugged in overnight.
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