how long you have been working with them? if you finish your 1 year or 2 years contract with them, then maybe you can ask them about your airfare if you did not fly to your home country yet...
End of the day you have to be with it as mention in your contract, if you are less then the time frame.
so 1st let us know how long you have been with them and if they hire you from Qatar or from your country, then its will help to reply you back ,,,
Regards