Ban entry from Singapore

I had been working in Singapore for half years, and the director reported me that i in a relationship with a man who is legally married in Singapore. 

So now the problem is, i can't even apply WP in Singapore also get ban for entry in Singapore.

Just wonder, how long it take for ban me to entry in singapore? In future, is that i still able to apply for WP and work in Singapore?

Sorry, didn't get you. Who banned you and for what? (Your profile appears as you are a Singaporean)

As far as I know, having an affair (even to a married man) is not illegal in Singapore.
So you must be banned for something else.
In any case, contact ICA to find out why and how long you are banned - and stay elsewhere until the ban is over (usually a few years).

Hi. My profile is wrong because I cannot find the Singapore forum at first.

I worked with the company, and the director report me having an affair with the a legal married man.. which mean I  had breached the Conditions of Work Permit under Fourth Schedule, Part VI, condition 8 of the Employment of Foreign Manpower Regulations (EFMR), which states that a work permit holder shall not be involved in any illegal, immoral or undesirable activities, including breaking up families in Singapore.

I get this details from MOM due they cancelled my permit and also don't let any company appeal for my case.

Just wanna ask that how long I will get ban for this kind of case?

As I said, usually a few years - but you should contact the authorities to find out.

Ya. Waiting MOM to reply me.

Here's another question, is that i will be hard to get WP after the ban time?

That depends on how severe your offense was.