Unwanted “Sign-In” with PW to my page

Hi,
I’m using Post Grid #2 on my page: https://www.gietl.earth/interieur/ and now I’m realising that people have to login with a PW in order to turn pages (previous, next, page 1, page 2).

See also: https://snipboard.io/LsVb1c.jpg

I checked the settings of PostX but I could not find a hint that I set this login.

What is wrong here?

Greetings, Maria

The page I need help with: [log in to see the link]