There's a travel bug: Whenever I travel for a while, I'm uphold by an invisible barrier. witch cause mobs within to be immobile, also: nearby waters give away to normal gravity (no swimming) while the player still gets drowning damage.
(No screenshots available as my security settings prohibit me from sharing)
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-38868.
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