Changed cracked screen and frame. Proximity sensor doesn't work

I ordered a replacement screen and frame (screen mounted to frame) from aliexpress. The assembly seems original and recovered from another phone.

Everything works well except for the proximity sensor, which always shows NEAR or INIT in the Service Menu - Auto Test. I think when it shows init it’s a contact problem as also the light sensor doesn’t seem to work.

I tried cleaning the screen where the sensor is and removing the protective film, but it always shows NEAR.

Any suggestions? Is the sensor defective? If so, I still have the one from the old phone, but it seems embedded between the screen and frame and wouldn’t want to pry apart the screen from the frame.