So,if somebody interested,this is what i found: it is known as singapore merchant token, or also known as singapore/malacca keping. the coin was circulated around 1831 in malaysia,singapore and sumatra. this is a coin minted by soho mint,birmingham on request by singapore merchants for trade purposes as british technically did not have a colony at that time in malay peninsular. singapore merchant token is worth around 100 - 150 usd in unc condition. only the 2 keping variety is expensive other varieties are cheap but the unc ones are hard to come by as it was heavily used for gambling in later days. the coin that i have is struck on 1799 half penny by the mint workers for amusement purposes.and usually was used as good luck charm by gamblers. (for information spacial thanks to mashe8786) i found similar "error" 1804 sumatra token,estimated Price 500-600 $ (not sold) i Want to Thank everybody for help!