Reject signed job because of EP long application
 

I got an offer from Company A in June and my EPass was pending since June till early December. While waiting for EP, I was worried since taking too long and I started looking for Job again. Now I got an offer from Company B and at the same time EP for Company A is approved.
I am more drawn towards B now since waiting for A for a long time and my project was changed also.

Therefore, I reject Company A and I explained to them well since they ask me why I want to change. but now they don't reply to me.

I need them to withdraw my EP application to proceed with Company B.
what should I do?

You wasted Company A's time for 6 months, and also all the admin hassle their HR has to go through with ICA/MOM and somemore now they have to restart the whole recruitment process again and don't know need to wait how long.

Don't expect Company A to go easy on you.

As a foreigner looking for a job here and relatively junior level (I assume below PEP level of 18k salary) you mess with them like that and expect them to just happily expedite your hopping to another company? Where got such free lunch in this world?