With the port flap removed you can put your screwdriver away. Focus on that metal clip looking piece

This metal clip is what provides the spring action to the port flap door. Overtime, it receeds further into the camera body, reducing the spring tension on the port flap door.

To put more spring action into that door, simply pry a bit up on that metal clip. Pry up, in the direction orthogonal to the camera, out-of-the-page.

Pull up lightly. Don't go crazy and pull too hard, as that metal clip can break from being over stressed. Be generous and take your time.

You do not need to remove the entire port flap assembly, like in the last 2 photos of this step. It is unnecessary.