SYNCHRONY BANK Overcharged me on Automatic payments. Did not honor 2 promotional interest free charges (Blamed retailer for not entering promotional codes) Orlando Florida

1) I was overcharged by Synchrony Bank via automatic payments.

The monthly automatic payment amounts varied from

$135 paid 7/2/2019

to

$185 paid 1/2/2020

When I asked to speak w/Supervisor NONE was available.  Their customer service number keeps you waiting for over one hour.

Tried to resolve via chat.

To add insult to injury only chat w/Robot NOT A LIVE CHAT Supervisor.

2) Synchrony Bank would not honor the 4 Total promotional interest free charges.

Only would honor 2 promotional interest free charges...putting the burden on me to 

secure the vender USES THE PROPER Promotional codes when entered into billing system.

3) interest rate on my balance is 24.99%

PLUS

3.25% interest rate!

***No supervisor to help me untangle this mess Synchrony made in their $favor.