Sometimes when coming through portals instantly kills you and your items are gone

How this is happening is basically sometimes, its happened to me and my friend is that when coming through a portal instantly "suffocates you" and your items are gone. I've searched for them and could not find them. I multiplied my nether coordinates by 8 in order to get my overworld coordinates in case it spawned a new portal and nothing was there. my friend is on switch and I'm on an android tablet vers 8.0 so if you could please fix it I would appreciate it