When I leave a world in 1.16.5 or 1.16.4 it does not save any changes.

Some worlds do not save at all and others save region file changes but not changes to player data.

When I load the a world i get two errors similar to this for each chunk
Couldn't load chunk [27, 12] java.nio.file.AccessDeniedException: /Users/myname/Library/Application Support/minecraft/saves/parkour_testing/region/r.0.0.mca at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84) at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102) at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107) at sun.nio.fs.UnixFileSystemProvider.newFileChannel(UnixFileSystemProvider.java:177) at java.nio.channels.FileChannel.open(FileChannel.java:287) at java.nio.channels.FileChannel.open(FileChannel.java:335) at cgy.<init>(SourceFile:128) at cgy.<init>(SourceFile:111) at cgz.b(SourceFile:43) at cgz.a(SourceFile:50) at cgv.b(SourceFile:85) at cgv.a(SourceFile:120) at aog$b.run(SourceFile:54) at aoe.e(SourceFile:94) at aoe.a(SourceFile:137) at aoe.run(SourceFile:105) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745)
And

Failed to read chunk [25, -27] java.nio.file.AccessDeniedException: /Users/myname/Library/Application Support/minecraft/saves/parkour_testing/region/r.0.-1.mca at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84) at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102) at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107) at sun.nio.fs.UnixFileSystemProvider.newFileChannel(UnixFileSystemProvider.java:177) at java.nio.channels.FileChannel.open(FileChannel.java:287) at java.nio.channels.FileChannel.open(FileChannel.java:335) at cgy.<init>(SourceFile:128) at cgy.<init>(SourceFile:111) at cgz.b(SourceFile:43) at cgz.a(SourceFile:50) at cgv.b(SourceFile:85) at cgv.a(SourceFile:120) at aog$b.run(SourceFile:54) at aoe.e(SourceFile:94) at aoe.a(SourceFile:137) at aoe.run(SourceFile:105) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745)

And when I leave a world I get this error for every chunk
Failed to store chunk [-12, 25] java.nio.file.AccessDeniedException: /Users/myname/Library/Application Support/minecraft/saves/parkour_testing/region/r.-1.0.mca at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84) at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102) at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107) at sun.nio.fs.UnixFileSystemProvider.newFileChannel(UnixFileSystemProvider.java:177) at java.nio.channels.FileChannel.open(FileChannel.java:287) at java.nio.channels.FileChannel.open(FileChannel.java:335) at cgy.<init>(SourceFile:128) at cgy.<init>(SourceFile:111) at cgz.b(SourceFile:43) at cgz.a(SourceFile:61) at cgv.a(SourceFile:144) at cgv.b(SourceFile:134) at aog$b.run(SourceFile:54) at aoe.e(SourceFile:94) at aoe.a(SourceFile:137) at aoe.run(SourceFile:105) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745)
I am using an Apple computer on an administrator account.
I have changed the file path in the errors as to avoid using my real name.