I'm pretty convinced it must be the data usage and have disabled all mobile data on my phone for the moment. Thanks for the info.

I bought the card in Kunming, so I don't think roaming is the problem. I think it's the data usage that sucked up all my credit, but will have to get the itemised bull to confirm. Thanks for your input anyway.

Thanks for the reply. I'll try that store or another big branch with such machines.

Hi, I was wondering if anyone knows how/which branch of China Mobile can provide itemised bills? I'm a prepaid customer, but for some reason my credit has been sucked up and I want to find out why. I went to a small China Mobile branch near where I'm staying, and was told they don't process bills there, so I would have to go to another. Does anyone know which types of branches, or which branch, could give me such a bill?

Thanks in advance.