Your carrier may charge for SMS message for activating iMessage

Dear all,

I am Akhil and I'm from Kerala , I have bought I phone from Qatar and used there for around 1 month now I'm on my vaccation and using iPhone here in Kerala. I am facing problem with my iMessage service by apple I have lost around 100 INR for activating iMessage (I believe still it's not activated ) in a day around 8 pop up message will come for activating the iMessage service and each time I press ok then it is the deduction of 5 INR from my balance ( that means I have activated it around 20 times!!!) still the polo up is showing ! Can u please help me to solve the issue ?? I'm having iPhone 6s ! This is the first time I am facing a issue like this from apple ! Hope they will guide me and solve the issue ASAP