When riding a boat, once you get out of the boat, the boat will disappear. Half the time, you can move below where the boat disappeared, and it will reappear, but half the time, it does not come back whatever you do unless you leave and rejoin the Server. Then it reappears. However, sometimes even when you leave and rejoin the server, the boat does not reappear.
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Thank you for your report!
We're tracking this issue in MCPE-125388, so this ticket is being resolved and linked as a duplicate.
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