I updated my world from 1.16.5 to 1.17 and I have this bug which at spawn (the mushroom island) the blocks that I place or remove revert to it's original state when I log out and log in. Video: https://www.reddit.com/r/Minecraft/comments/nvvmyf/blocks_not_saving_in_my_singleplayer_base_117/
World link: https://drive.google.com/drive/folders/1rXClSgqmucCUKZrAuifFHBv-x05xvTmd?usp=sharing
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here is the crash report and here is the world file: https://drive.google.com/drive/folders/1rXClSgqmucCUKZrAuifFHBv-x05xvTmd?usp=sharing

Might be a re-occurrence of MC-216148.
I haven't played in the snapshots, I updated my world from 1.16.5 to 1.17

It's probably not the same issue then.
I cannot access the world download link you posted.
Thank you for your report!
We're tracking this issue in MC-228113, so this ticket is being resolved and linked as a duplicate.
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We do not have enough information to find the cause of this issue.
Please attach the affected (zipped) world file. If the file size is too large, please upload it somewhere else and then link to it here.
This issue is being temporarily closed as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.
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