Dear teacher please correct if it is not.

As usual you send me a consolidated amount in advance for your personal expenses. When the amount spent on your personal expenses then we would send you a detail of expenses.
The latest amount which we received from you was Rs.500,000/- on 2nd July 2013. After that we have not received any amount from you. we have been sending you month expenses statements since July 2013. Your balance is reached excess by 25,000/-. So now we need further 500,000/- as per the following break up 25,000/- against outstanding balance & remaining balance of Rs.425,000/- treated as advance for your personal expenses.
Do you know we are short in cash since for a long time? If we have sufficient cash with us, we will pay your bills first and then claim to you. We hope you will understand our position.