Problem with delete “Under construction” page

I installed the plugin “Coming Soon Page, Under Construction & Maintenance Mode by SeedProd” and put page “under construction” (even with a countdown)
When I wanted to remove this page it CANNOT.
I already emptied the site cache, even manually on the server (including hidden files), there is no “maintenance” page in the root of the site.
I already removed the plugin
I already installed one and two plugins to clear cache.
I no longer know what I need to do, what can I do to get the construction page deleted?

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