Incentive removal legal or not?

I was receiving a 5k incentive every time we hit our monthly target. But now we have a new boss in the company and he said that he will have to stop the incentive that we are receiving because with or without the incentive our priority is to hit our monthly target. Is this legal to do this or should I seek DOLE for help. I was not yet regular in the position but in my previous position I was already receiving a 3K monthly incentive. I've been in the company for almost 6 years now and it was the common practice before to give us incentives, I started at 1K monthly and then 3K and now I'm at 5K because I've been getting a promotion in my position. Your immediate response would be greatly appreciated. Thanks!

company discretion po yan..

kung common practice na ang pagbibigay ng mga insentibo at wla namang pagbaba sa kita ng kumpanya.... ang biglaang pagtanggal ng mga insentibo ay abuso ng discretion. itoy labag sa rule ng "non-diminution of benefits".