Airtel — international roaming data charge is way high

Hi,

I have been using my airtel international roaming from april 2018 in china. I took a plan for 3999 in which they mentioned that i will get a 5 gb internet every month. Now yesterday i received 3 messages, one said my data usage went to 7737, then later again i received a message that my data usage went to 10254, then again today morning i received a message that my data usage went to 21474. I am using a china unicom number as well which i took it in april a local number and they have given me unlimited data usage. I am using that only. I don't understand why i am getting charged so high. Also on top of that yesterday i called the airtel customer care when i received the message of 10254 and i asked them to block my internet services asap. The person on phone confirmed me that my gprs services are blocked and it will be effective in 30 minutes. I also have that message that we have activated the data barring. But these fools have blocked my incoming and outgoing calls and my internet when i checked it is still working. I will be coming to india in novemeber and i will take them to court for sure. They are just cheating customers.