Mobile Nether Bug

There is a bug with the Minecraft mobile nether every time I go in it takes away my hud and puts a loading bar on my screen and I have to restart my Minecraft and it’s usually is fine but this time I brought my diamond pick with the fourtue enchant with me and it gave me the loading bar so I restart my game and when I did the pick was gone so I looked in the chest where I stored it not there so can you please fix this bug so I don’t lose more stuff and I can get stuff from the nether.

 

(Sorry don’t have video or screen shot)