Synchrony Bank Credit Card Complaint

Synchrony Bank Credit card department,

Customer service / Customer relations Kentucky

I have a store credit card with Walmart. Several months ago, I had a balance, but because I was about - days late, they took about half of the amount as a late fee, instead of charging it to my account. This month I went over my balance - $2400.00 - by $53.00 and change, and got a payment due of about $170.00. If I had not gone over, my payment would have been $68.00. I do n't think they should be allowed to charge the consumer like this. I sent an email for an explanation of why they charge like this, but so far no answer.