Unable to complete Jetpack setup

Unable to complete Jetpack setup
The page load time has increased many times over on the page

Here you can see what’s on the screen, see the link

https://www.stalemladi.cz/d/obr/error.autorizing.jpg

It then redirects to the page

https://www.stalemladi.cz/wp-admin/admin.php?page=jetpack&connect_url_redirect=true&jetpack_connect_login_redirect=true&jetpack_connect_url=https%3A%2F%2Fwww.stalemladi.cz%2Fwp-admin%2Fadmin.php%3Fpage%3Djetpack%26connect_url_redirect%3Dtrue%26jetpack_connect_login_redirect%3Dtrue&calypso_env=production&auth_type=jetpack&from=landing-page-bottom&redirect_after_auth=https%3A%2F%2Fwww.stalemladi.cz%2Fwp-admin%2Fadmin.php%3Fpage%3Djetpack

and the inscription appears:

You do not have sufficient permissions to access this page.

Please advise

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