All URLs are having ‘/blog/’ appended to them.

Pages don’t have a base in the URL unless you are associating the page with a parent in the “Page Attributes” section. Example:

Page 1 – “Contact Us” (no parent)

Page 2 – “Directions” (Contact Us as parent)

Page 1 URL – domain.com/contact-us

Page 2 URL – domain.com/contact-us/directions

Also, are you sure you’re dealing with actual pages and not posts in a category?