Typically that challenge occurs when the browser has no cookie saved from a previous eBay session, or when using a different IP-address. It is not normal for such challenges to occur when going to different pages after having successfully signed in.

Have you changed anything about your setup lately? New browser, or new privacy software or settings? Using a VPN or hotspot?

If nothing has changed about your setup, you may have a problem with an eBay cookie that is corrupt or blocked.

Try another browser altogether or a private or incognito browser window.

Preferably the latest version of a browser you have not used before, with default settings and no add-ons installed.

If you can navigate without repeated challenges in another browser, try manually erasing eBay cookies once in your original browser.