Die while pillaring up in the nether

I am playing Minecraft bedrock edition  on IOS with the caves and cliffs beta.  While pillaring up In the nether I died  due to fall damage even though I did not fall.   When I went back to the area where I died everything in my inventory de-spawned and the pillar I had made was gone.   I went back and tried pillaring up again, and the same thing happened.