Unhappy customer

I have been requesting TFG company to update my surname on their system and they refuse. It has been 3 consecutive months and I have been to American Swiss, total sports with both of my Id's but still I'm not winning. Every call I get from the call center agents I'm being addressed with my incorrect surname. I have been in contact with about 30 agents already but still no resolution to my query. As a customer I have a right to change my personal details but with them am being denied. I want this matter to be sorted ASAP.