5 months? 5 MONTHS? you waited 5 months with 50% of original salary? Are u crazy? Why did u accept the new contract?
No offence to you or your kabayans, but you people need to be a bit more aggressive when it comes to these things. I see it in the company i work. Same things...
But nooo.... you just bend over to whatever the employers is giving you. You need to stop taking s*** from others and be more aggressive... otherwise they will keep on taking advantage of you. BTW they will not increase anything since you already accepted the terms of the contract.

Going to the Labour Commission is useless since your contract is already signed (that means you agreed to the terms of the contract + salary and benefits). What you need to do now is just finish the contract and after that ask them to send you home. If they tell you again to stay and wait, then you go to LC and make a complaint. END OF STORY.