Getting Transfer certificate

Sir/madam My son has completed 7th from a CBSE school.we wnat to put him in a different school.Now the CBSE school made all payments or requisition through only online. But the problem is the particular school app and portal is not working properly many a times. Everytime we have to wait and do it. . Regarding TC , We received a mail stating the TC requisition can be made through portal which is open between jan 5 to march31 2018, conditions apply. Whenever i tried the portal not opened. In 3rd week of march i called the school office and asked "since the school is going to close by 23 rd when can i collect the TC. They said only through online we can apply for it .but again i could not suceeded. I went asked in person. The school authority said even if i apply now in online i have to pay Ist installment school fee and book fees which come to Rs.40,000/.And moreover our refundable deposit Rs. 40,000/ also with them. 25th of march is last date for 1st term payment but online payment portal not working yesterday. I am totally stressed,. Kindly advice me how to proceed with