A bad day in my life to be member of this bank! Ea...

A bad day in my life to be member of this bank! Earlier payment was withdrawn within 2-3days, this time they pulled in 9 days later. And put my account on post mark, also lower my score by 136 points. Is this sounds regional. I called them they said late payment. But I send the payment a week before the due date. They obviously tried to put me down. So what is next do I need to do let me support and suggestions to resolve this issue! Hope it worth to me.