Lava does not flow

What is the randomTickSpeed gamerule set to? You can find out by doing /gamerule randomTickSpeed

Might be a desync caused by MC-12363. What happens if you relog? Does the issue remain?

Also, did y ou disable the vanilla data pack?

I will try logging in soon

If I throw items they disappear
Commands do not work
When I leave world game freezes
I want to delete it

Could you leave a link to the world file?

I will do it later on the weekends