As you have worked for three and a half years, the end of your contract has become the end of your work permit and is no more according to the period written in your contract. Therefore, to ask for legal termination, you must wait until that date. Do not resign or try to leave work now, as you will be considered as having violated the contract and the law. ESB is calculated on the basis of the Last Monthly Wage (LMW), which is your last salary plus all other allowances, such as housing and transportation. For each of the first five years, you will get half LMW, and for any part of a year you served you will get ESB proportionately. If you continue to work after that, for any year beyond five, you will get a full LMW as ESB. After you terminate your job, you may look for another employer if your present company does not mind. It may even help in transferring your iqama to your new sponsor and will encourage him to do so if you get a job in another type of profession that does not compete with his business. At the same time you may try to negotiate with him by letting go some of your present rights, such as air ticket, or part of your end of service remunerations. It is up to the sole discretion of your company to give you a NOC, even if it does not require you to continue to work for it. If your company will not cooperate, you will have to leave the country and will only be able to return to another job after one year.
 

 
Why would your sponsor report you as an escapee unless you have perhaps disappeared from work? But let us take your word for it. In this case you have nothing to fear. Take your papers to the Labor Office with an Arabic translator and complain against what your sponsor has done. Show proof that you have not broken the law. The Labor Office will help you by calling your sponsor and will investigate the matter in your favor.