After multiple months of flights EKF2 stopped working with vision/pose inputs

Hey, today I ran into a crazy issue and I don’t know how to proceed.
For quite a while (I would guess since summer) I used two PX4 drones (with pixhawk 2.1and with master-branches from summer) in our indoor flight area. Motion capture system provided position data which was published via an onboard computer (RaspPi) and mavros. Everything ran fine and I had no issues with this setup…

But yesterday my drone had some flight issues - position hold did not work properly - and while landing the drone was knocked over… not harsh but lightly. So I fixed my rotor guards and tried to fly today again. Today I realized my mavros/local_position/pose doesn’t publish anything for x/y positions. But my vision_pose input and even my mavlink inspector are showing correct inputs.
Upon mavros-launch I have for maybe 5 seconds some x/y positions while my EKF2 is initializing but afterwards just plain zero’s and moving the drone doesn’t change anything. So it’s not running correctly, like the pixhawk/px4 doesn’t care about the vision_pose.

Does anybody know what’s going on?
I feared maybe something with my pixhawk is wrong, so I took the other drone but same issue. Next I changed the cable connector between Pi and Pixhawk but still the same issue. I even changed the Raspi but still the same issue. I did recallibrations and restarts and right now I don’t know what to do. Last flight was on Thursday and everything was fine then…

So if anyone had a similar issue or an idea how to solve it - I would be very grateful

Kind regards