Rangefinder engaging at wrong altitude

Hello Ardupilot community,

False trigger of the Q_Land_Final_Alt.

VTOL Setup:
Auto mission
Q_Land_Final_Alt : 5m
Q_Land_Speed : 0.5m/s
Transition Altitude : 40m
Rangefinder: TF mini Plus

Problem description:
After transitioning from Plane to Quad, the land speed is set to 1.35m/s and Q_land_speed should be triggered 5m above the ground, but Q_land_speed is triggering much before (30-20m from the ground).

Log screenshot for reference:

As we can see, there is a lot of spikes from rangefinder data. What can cause these issues ? And how can I solve the it ?