Error with VR - Assertion failed: !IsUnreachable()

Hello all,
I am actually working on a vr project, and sometimes my project built crash with and error message (see the screen capture).

How can I solve this problem, I am using my old vr MotionControllerPawn in the 4.19 version, this can cause issues?

Tks for your help.

PS: the message error is : Assertion failed: !IsUnreachable()