Vodafone — fresh recharge are already used

dear sir, madam,
i m selling the vodafone last 7 yrs.i have sell 5-10 sims daily on my counter.my sail of vodafone is app. 10000 daily.here are the fresh recharge sheet of recharge of rs.10 is alredy use.i have call the rm os silawar enter.shamliand tell him about this matter.he replys me that what can i do?he says that here is a laser pen in the market, from this pen we can read the screch no.of the fresh recharge coupon.i have suffer this problem 3 times in last 1 year.last recharge of rs 10 sheet i have send it to silawar ent.shamli.gurusharan says that you give me the sheet of recharge.and i will give you the fresh sheet.i want to know that how does it possible?after that gurusharan talk me with rm bharat dua.he tells me that i have change this sheet but in the future after the date of the bill i cannot do anything.plz give me solution of this problem or i have going to consumer coart.plz cont.me at my cell no.[protected], [protected].