Missing data and rude call center agent

I called the 111 call centre to find out about a call back I was expecting from a boss as per the previous call I made earlier on regarding my data and airtime that went missing, I wanted to find out what exactly happened to my data. The second call I spoke to a Tasmin am sure that call can be listen too, she denies saying what she said to me when I repeat it and she is very rude and she dropped the call while I wanted details of her Team leader asking me why i want those details. I still want to know what happened to my 500mb and still waiting for a call back from a boss who probably won't bother to call me back because Tasmin said the first agent I spoke to gave me wrong info which she denies she said and she hangs up with her stinking attitude.