Warning: Unnecessary HSTS header over HTTP

Using this test: https://hstspreload.org/?domain=detektywtd24.pl
I get:

Warning: Unnecessary HSTS header over HTTPThe HTTP page at https://detektywtd24.pl sends an HSTS header. This has no effect over HTTP, and should be removed.

What can I do about it? What causes it?

• This topic was modified 2 years ago by Adam.

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