Hitman 2 Mastery Achievement

I’ve completed Mastery level 20 in Bangkok and haven’t unlocked my achievement on Xbox one. I reached level 20 around a week and a half ago and still nothing, I’ve tried doing more challenges inside the map but i’m slowly running out of challenges to do.I did reach 20 inside the bonus mission as i didn’t know there was an issue but online people say that it was patched in December however i’m not the only one still experiencing this issue. Any help would be great, thanks. its the only thing stopping me from 100%.

If you mean House Built on Sand mission, if I recall right, developers know about it.

Still, you should write about this in official bug report thread so the developers could see your message.
Here’s the link, post it there: