Ok i cannot leave beta, im writing ticket again.. i did this:

How to Leave the Beta

1. On Xbox One or a Windows 10 PC, sign in with the account that registered for the Minecraft Beta and launch the Xbox Insider Hub.N
2. avigate to Insider content > Minecraft (or Minecraft for Windows 10 on PC)
3. Select Manage.
4. Use the radio button to select Unenroll (Leave this preview), then select Done.
5. Wait an additional 30-60 minutes after unenrollment completes (Pending no longer appears in the Xbox Insider Hub).

Uninstall and reinstall Minecraft.

Minecraft Beta FAQs

I’m trying to leave the beta on my Windows 10 PC, but the beta still installs even after following the steps to leave? 

Very rarely this can occur on Windows 10 PCs when multiple accounts have signed in and played the game. In these circumstances, try the following steps:

1. From the Search bar on your Windows 10 PC, type “Command Prompt“F
2. rom the search results, right click on “Command Prompt (Desktop app)“
3. From the context menu, select Run as Administrator.
4. Select “Yes” if you are prompted with “Do you want to allow this app to make changes to your device?”
5. In the Administrator: Command Prompt window, type powershell and press Enter.
6. In the Administrator: Command Prompt window, type Get-AppxPackage -allusers minecraftUWP | remove-appxpackage -allusers and press Enter.

but its not working so i will be gratefull if someone will not post this, because it;s not working....

AS you can see at the pictures, i left the beta. Wrote even code Get-AppxPackage -allusers minecraftUWP | remove-appxpackage -allusers in powershell, reinstall minecraft. Still nothing

If u will not show other solution that all above what i did, please dont close the ticket.