I know most people don't play on old worlds anymore, but some people like me are kind of a hardcore nostalgist, I usually only play bedrock exclusively for this feature.
Unfortunately there is a bug in old world types where if you are on water near the world border, you will not be able to jump up onto land at all.
This bug also affect certain objects such as stairs where instead of automatically going upwards, you would have to manually jump up the stairs.
I have tested this on multiple old worlds and this bug is consistent beetween all of them, this bug will only happen in chunks near the world border.
Thank you for your report!
We're tracking this issue in MCPE-42058, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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