help me find this manhwa

it's in a historical setting and the mc is this sort of "officer" but like these officers are kind of rare so the king gives them this sort of medal to prove their identity. but mc is kind of dumb so in the first few chapters he ends up getting SA'd by this old perv cuz he reveals his identity but no one believes him...ml is there too but he's a lot more cunning and he also has the badge but i think he doesn't reveal himself pls help bro