Can’t add services posts in menu

Hey, I have a problem with adding services to my menu. On my website I downloaded my theme that uses elementor, and the themes comes with 4 pre-made service pages. In the main menu under “Services”, these 4 service pages is visible: https://pasteboard.co/UXTeZ9DJFMRp.png

However I then want to add 2 new service pages/posts (https://pasteboard.co/FJAmiEGD7KUZ.png) and also add them as sub-items to the Services menu, but I can’t figure out how to do that: https://pasteboard.co/Wg0Pv0adWQrx.png

The Services pages do not appear in the menu settings. What is the way to do this?

Kind regards
Youssef

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