MTN customer service

I lost my simcard now im calling MTN to block the number as the simcard now is beeing used by someone I dont know and that person is busy harassing my contacts. MTN is saying I need to visit the branch, where I stay there is no MTN branch its very far away from me. My question is by the time I get to the branch who knows what this person would have done with my details. Does this mean MTN does not care about people living in remote areas where there is no branch if when you call customer service they mention things of visiting the branch?