Refuse to connect my dstv thought payment was done

I paid them last month on the 19 of March amount of 540 that payment was supposed to be paid in the 2nd of April I paid them early since bigining of April they been carting my view they said I owe them. I have send my proof of payment they refuse to connect my dstv. My references for proof of payment is ***0 They rob me my money because now they are saying I owe them 610 I have bought more than 400 of airtime just to call them