Hello,

I saw the screenshots you attached.

This is something to do with the permalinks.

Please try setting permalinks according to your needs from Settings >> Permalinks. Then try re adding the product link to the button then clear cache and check back.

You can read the following article for further help:
https://www.wpbeginner.com/wp-tutorials/how-to-create-custom-permalinks-in-wordpress/#what-is-custom-permalink

Best Regards.