Once you have entered an agreement with company to serve them for a period of two years, you are required to serve the said period in normal course. However, you are telling after serving for one year, you applied leave for 3 months on medical ground and after getting the signature on another bond, they sanctioned you leave for 3 months with a condition to complete the balance period of one year. On expiry of said leave, you have sent a message from UAE, requesting your management to extend said leave on medical ground for further period.
By that time did you send any medical certificates in support of your claim for your alleged sickness along with your mail or not? If you did not send any such certificates, management may be under an impression that your alleged sickness might not be genuine and as such they thought that in order to avoid balance period of notice you are requesting them for extension of leave on false medical grounds.
Under the given circumstances, generally, management requires to send a notice to you informing that your request for extension of leave was not granted and you were supposed to join duty on or before ............date or else it would be treated that you are absconding from duty and the same is liable for termination. After observing the procedure of issuing charge sheet for unauthorized absence and holding inquiry, they can terminate your services and then only they are having right to claim compensation from you for unserved period of agreement period that too after giving proper prior notice and if there was no response from you till date.
If you fails to respond to the communication of management at the address given by you while you were in India, it might have been one of the reason that management has filed a suit in appropriate court against you for recovery of compensation on the ground of breach of service agreement.
My advise is, if management did not follow the procedure in terminating your services as stated in spite of having proper reply from your side to for the communication of management from time to time, you should contact labor law consultant / advocate in Kerala / any other place where you are living to get the justice.