No RTL with OPTICAL FLOW and GPS in LOITER mode

Hi all,

I tried a flight with optical flow CX OF clone sensor and GPS COMPASS active. The quad flies quite well even if there are vibrations when turning yaw. These vibrations are not present without active optical flow (probably because there is no Y pin connected on the sensor). But the biggest problem is that RTL no longer works than before, without active optical flow, it worked well.
For what reason?

I attach the flight log.

Thank you