Big Bazaar / Futurebazaar / Future Retail / Hometown — mrp mismatch and wrong price charged

Address: Big Bazaar, Rave@Moti Mall, Rawatpur Crossing, Kanpur 208025 UP

Dear consumer forum, every time whenever i purchase from big bazaar, it has been noticed that they charged the wrong amount at higher side and whenever i noticed and complaint about this then they apologies and accept the mistakes and refund the difference amount. I felt that it is in their use and regularly they are doing it and if customer noticed then they apologies and refund and difference amount.
Tell me what should i do if again they will do the same kind of thing, i have all their mistakes and acceptance in written form.

Regards,
Anand k sharma
Kanpur-up