School Insisting on next year's fee payment to issue TC

Our 2 kids studied in Birla Open Minds school in Hyderabad and we decided to shift them to other school due to personal reasons. We applied for TC on January 17th when the school opened after makar santranti holidays after we enquired about the process from front office of school who told us to apply on their smartphone app. School is now refusing to issue TC stating that 13th January was deadline to apply for TC and since we applied on 17th January, we are liable to pay them fees for 1st term (4 months) before TC can be issued. We told them we applied for TC on 17th as the school was closed between 7th to 16th January and once school opened on 17th we enquired about process for TC and applied same day so it should not be counted as delay. They are not responding to our emails and on phone they are arguing that multiple emails were sent regarding policy around TC so nothing can be done unless full term fees is paid and they are using this so called delay of 4 days (when school was also closed) as reason for this. What are my legal options here and how can we stop them from extorting money like this?