Password protected not working

Hi,
I’m using Password protected pages on WordPress but I have a problem.

When I select a password and I save, me, as an admin, I can see, write password and website confirms it’s correct.

But if I try to enter on incognito, sometimes website is skipping the password step, and other times it show it but it’s always incorrect.

When I clean cache, usually website skips first password step. When I refresh the password, saving the product, I ussually get the second scenario.

Any idea why?

Many thanks!

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