Guys i was coding an rental management for my friend .while selecting each renter's view page it display renter full detail in on table , payed_date and payed_rent amount detail and total of remaining amount he payed.But the problem is that while entering payed_date and payed_rent amount twice in one month the payed amount substract twice from rent_date.how can i rectify this problem in php coding skill.please find any way