Megamenu and off-canvas both shown in small responsive state

Hello,

I use a megamenu and off-canvas. Off-canvas is for small screens. I followed toy video tutorial for the right settings. Except de small state works not good when I disable the position from megamenu and enable the off-canvas in the responsive small state both menu's are shown in the small browser state on the frontend.

When I do the settings vice versa (megamenu = enabled and off-canvas = disabled) then it works good. I only see the megamenu then?