Working for 2 Company without informing during Job Offer

Patulong naman po.....Na hire po ako pero hindi po nabangit sa akin na dalawang company pala po ang tatrabahuhin ko, kasama yung Holding Company. Ano po kaya ang habol ko dito?

Check the employment contract that you signed. You have the choice whether to continue with your employment or not.

Hire na po ako nung malaman ko. no choice po nag continue pa rin ako kaso masyado na pong lumalaki ang bulk ng trabaho and masyado na po silang demanding for the other company....pwede po ba akong mag demand for additional pay?

You actually did not answer my question. Did you read your employment contract?

There is usually a clause included there that you could be assigned to perform any lawful task that the employer would ask you to do.

If the scope of the employment did not include doing work for the holding company, that is the time you can ask for additional pay since it is not included in your original contract.

it doesn't matter. even without a contract an employer is within his rights to instruct his employee to perform duties for any entity they so wish. parang cashier sa jollibee, lahat ng customer nila ay kelangan paglinkuran.
If you are an accountant, if your employer wishes you to do the books of 100 companies you have to do it. if you need more than 8 hours to do it then they should pay you overtime but anything that can be accomplished in 8 hours you cannot demand any extra salary for it.
same pronciple as if you are a janitor and the company asks you to be a receptionist or utility man. as long as you are qualified they can ask you to it. no extra compensation needed.

kung ayaw mo sa ganitong systema you can always resign. no company would want you anyways if they find out you have this kind of attitude

kahit 3 company pa yan, walang kaso yun.. pinapa sweldo ka naman nila.. kung sosobra sa 8 hours ang trabaho mo then demand for overtime pay.. kung ayaw mo nang trabaho.. pwede ka naman mag resign..