Reducing of carbon emission on my 2006 Honds XR125L

So where im from (Singapore) we're required to pass a yearly inspection, one of the tests include a carbon emission test where they insert a probe and idle your bike for a few seconds.

Passing is 0.1% but mine was 0.9%. https://imgur.com/a/ZKBCGJv

I have no idea what to do or what the problem is as my bike is fully stock. The engine was overhauled 2 years ago by the previous owner. I've literally only had this for 6 months. I have to pass this by next month or they will destroy my bike.

Any help is appreciated.