Videocon D2h - Charged twice for single service

I was having issue with my d*h connection so I called their customer care for help they told me they will send their engineer to fix the problem with my connection and they will charge ₹*** for the visit and also informed me that if I still face any problem with my connection then next visit of their engineer will be free for next * month. I asked their engineer to visit my place and fix the problem but their engineer didn't come and they still charged me for the visit which really never happened. I contacted customer care regarding deduction made they assured me that they will send their engineer again to fix the problem with my connection and they will not charge this time. This time their engineer came and fixed the problem but when I again recharged my account they again deducted my account balance for the visit even after reassuring me that this visit won't be chargeable this time. Due to this, my account balance got nil and I am unable to view my channels. Despite my repetitive complaints, they are not refunding the amount that they have charged twice.