my game keeps crashing when i play in my a year and half old survival world on Xbox series x

Thank you for your report!
However, this issue is Invalid for the bug tracker.

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I am also seeing this on iPadOS. I am unable to confirm whether the crash logs are sent automatically (presumably a setting on iOS?) but can send the world in if it helps. It’s only about 20mb.  This is on iOS 15.01, Minecraft 1.17.34 with all vanilla settings - no experimental mode or add-ons etc. crash is reliably within 2-3 minutes of launch. 

I have posted this, not sure if it's crashing the same for you... Hope it helps.
MCPE-144052