Hi Venkatesh,

Colleges usually take some time to refund such amounts. However, if you want to get in contact with them, consider calling up these numbers:

0462-2912081, 82, 83, 84 & 85
044-22351014
044-22351015

If you are a resident of Chennai, you can even consider visiting the campus at the following address

Directorate of Technical Education (DoTE),
53, Sardar Patel Road,
Guindy,
Chennai - 600 025