Synchrony Bank Credit Card Complaint

Synchrony Bank Credit card department,

APR or interest rate California

My interest rate was increased without notice to 26 %, and I have had my auto pay set to pay whatever the minimum balance is each month, the idea was to help build my credit. After 6 months, I notice that I have been getting hit in $ - interest charges, some months I was charged - $ in just interest. When I called the Company today to find out why, they said I needed to pay the entire statement balance in order to stop the massive interest charges. Gave no reason as to why my rate changed and then the rep tried to tell me everyone 's rate is the same, then would n't explain why the minimum payment that their system sets, is n't really what I need to be paying or why they couldnt notify me about it. I have no late payment history with these people yet they told me they can not change my interest rate or work with me on getting this paid off.