Barclays Bank — credit card and over charge (fraudulent) on my account

Address:

560030

Barclays offered a credit card to me. I reluctantly made a transaction and made the payment promptly to them to clear off the dues, however, they charged me for late fees and interest charges without properly communicating to me on their dates. I requested them to reverse the same, but instead of reversing the amount they continued to add the and charge more to my account. I dont think that this is the right way to do business and that was why they were unable to survive even for a 2 yrs in india and now the account has been transferred to kotak and i am still trying to settle the account with them. Need help in getting my credit score rectified. Also, avoid using credit cards from any of the banks.