Policy "Corvée" not working (Not a Bug)

[Ludwig]

In one of my game, I am building Petra (a classical wonder) an the Corvée policy (+15% production for ancient and classical wonders) does not apply to my production.
I made sure to check one turn after I set the policy.
For the details: I am building Petra in a city that is not my capital and I am in medieval era (perhaps that is the bug?).

Anyone out there with the same issue?

 

[Exodite]

Are you relying on the production tooltip or manual calculation?

Because it's a known bug that percentage bonuses, like most policy cards, don't show up in the production tooltip/breakdown but they do generally get applied towards the relevant items.