I received interest certificate from SBI for 30 months old SBI max gain loan account. I found mismatch in the principal amount mentioned in it from my account statement. As per the statement, my drawing power has been reduced by Rs. 59,562 which I think is the principal amount that I have paid in last 30 months. Interest certificate shows that I have paid Rs. 98,556. What can be the reason of this mismatch and how to resolve it?