[Resolved]  HDFC Bank — Balance moves to negative

Hello,
I hold a salary account with the HDFC bank.But I resigned to my job and moved to further studies to USA. After that money is not getting credited into the account. Recently I again got a chance to work with HDFC bank by opening an NRE account and called the customer service to convert my account to NRE. They suggested to close the existing account and open a new account. When I observe my account by logging in I found out that the positive balance has gone to negative(-5000) and I again called the customer service and I was told that since there is no salary in the account it has been made a savings account.
I was not even informed about the account conversion in a mail or other modes