Paschimanchal Vidyut Vitran Nigam [Pvvnl] — About bill payment

Pl. Clearify why the cleark received payment of electricity bill amount shows of due date where as bill was paid well in time.
Receipt no.[protected] counter no. 15092211 collection date 19/07/2016
Account no.[protected] tender control id [protected] for rs 2923/ was paid
With in time, bill amount with in due dt. Was 2916/-and amunt after due date is
2923/-. Under which circumtances the excess amont rs 7/- was charged by your cleark. Pl. Solve the problem.