Idea Cellular — unexpected bill of 18000.my idea postpaid bill, please help me into this my number is [protected]

Address:

Nagpur, Maharashtra, 440027

Hello,
This is regarding my idea postpaid bill, Please help me into this my number is [protected].Few days before I got the shocking bill of rupees 18000.
On 30th of November I moved to Thailand and activated the ISD calling from the IDEA App. By activating this it charge me some 150 rupees this is ok with some other charges of calling which I will made.
I made few calls that is also ok. IDEA provided me with a fixed 3778 rps of credit limit. So when I am making the call it will debit the amount from my credit limit this is also ok and I am receiving the notification that you have used this much amount of your credit limit.
The final message I received from the IDEA is .you have used your 70% of your credit limit nearby 2000 rps. I assume that I have used so it is ok.
But suddenly my number get barded. i don’t know what happened and I am unable to use my number. When I came back to the India I have reactive the number and suddenly came to know that I have a unbilled amount of rupees 15000 and later again it changes to 18000 thousand I am totally shocked what’s going on. I made the call to customer care and they also don’t know what happened and they told me to wait till the bill generate. So I wait till the bill generate.
When the bill was generated the another shocking news I got due to the internet data usage I got this much bill. I asked the customer care and they told me I have used 18MB of data due to which I got the bill of 18000 rps.
Sir I haven’t used the mobile data. I used my hotel wifi internet only. Can you imagein what will happened in 18MB in this world. A single photo size is more than 18MB on internet. If I really want to use the data why it will be of 18MB.
They told me I use 5kb, 10kb, 3kb of data including all 18MB.This is unbelievable. In kbs a very old mobile also not use the internet in kbs.
First thing it should not cross my credit limit at any cost. The credit limit I have will be my final limit and it should not cross.
If this get cross the credit limit then what is the use of credit limit. Suppose I lost the mobile and someone else use the mobile and use of 1GB of data then 20 to 30 lakhs of bill come to me. Who will be responsible for this?
Second I did not received any notification of crossing the bill of 18000 due to internet.
So please help me into this. This is beyond my expectation and I am common man. I can’t bear this. I am ready to pay what I used that is calling charges but not the data usage which I haven’t use.

Sincerely
Badal Bhagat