I uninstall version 8.1.22 and then tried to install 8.1.2

but after uninstalling and installing the exact machine none of them started to work
is there any procedure to uninstall it entirely and clean install

To uninstall Ignition, you should just need to run the uninstaller file as mentioned in this user manual page. If you no longer need to keep files from the previous install, you can then delete all the contents of the previous install directory. If you're running into issues getting Ignition installed/started I would suggest reaching out to support or uploading your install.log and wrapper.log files to this thread.

When going backwards in versions, you need to have no trace of the later version. Delete all of the folders from the other install before installing another.