@dimitrios-kanellopoulos humm humm ⌠it was not my problem.
the situation was the following :
on the beach, I checked the watch both my current position which I marked as a POI and the compass, all was OK
I swim I swim I swim đ đ đ
On the return when I was able to touch the sand, I press a long time on the central button and activate the navigation to the POI I recorded before
What I observed then is the following
the compass screen was here with a correct distance to my beach towel
but the arrows both for north and target were almost at 180°
when I moved my arm on the left or right the arrows were crasy
(even not keeping the same direction but becomign a sort of erratic)
when I was moving in the direction of my beach towel, the distance was correctly reduced, still the target arrow was almost on the opposite side.
In such situation, there is no solution until and unless I stop the exercise â which I do not want â and at that time ask the recalibration of the watch
PS : I agree that when I swim and the arm is below the water, then the watch cannot process anymore.