Indigo Airlines — regarding the weight of baggage

You people are really fraud.. As per your rules and regulations 15kgs are allowed in check-in baggage and mine was less than 15kgs, still they charged me rs. 2100 for extra weight.. That time i was in a hurry because my flight was about to take off, that's why i didn't ask anything and just gave rs.2100.. Now only i saw that 15kgs are allowed.. Now i want money back else i will take strict actions against you.