O2 Remove Call Barring -

For most Android and Samsung devices, call barring is managed within the phone app. Solved: Call Barring - O2 Community Forum

From a technical standpoint, the system is robust. o2 remove call barring

For more specific removals:

This is the weak link. Many users turn to O2 customer support (Guru chat or phone) only to be met with confusion. For most Android and Samsung devices, call barring