I was going far out in creative for a build idea, and when I started to build the idea I had in mind, at water level (63Y) I started phasing through the blocks while halfway inside the water.
I'm not exactly sure what causes this bug (Maybe being far out from spawn?)
I was unable to replicate this again, it only happened the one time.
The video I had recorded is unable to be shared as the service I use isn't co-operating with me.
If you can replicate this bug and are able to get it on video, it would help.

Thanks for reading.