jQuery updater changes version only in filename

After installation of plugin all in webpage code seems to be ok. The library adress is: https://www.bezdroza4x4.pl/wp-content/cache/busting/1/wp-includes/js/jquery/jquery-3.5.1.js BUT inside this file is old library version 1.12. I tried to change it via FTP, but it is automatically replaced. How it is possible? I have flushed all cache (I think so). What to do?

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