First, please be sure you're the Admin of any Facebook Pages you want to connect. Because of the way Facebook permissions work, we can only publish on your behalf to Pages that you are the Admin of.
In addition to being Admin of the Page, Ripl needs permission from Facebook to manage your Pages. It's best to give Ripl permission to manage "All Pages" in Facebook. Otherwise new Pages created in Facebook and Pages not initially granted permissions will not be visible in Ripl. To correct this, please follow the instructions below.
Once you have completed the steps above on either your mobile app or on your computer, return to Ripl and tap the "My posts" tab, then select "Brand settings." You can then tap "Connect" next to your Facebook Page or Group. Do you now see the option to select your missing Page? If not, please reach out to our support team on firstname.lastname@example.org, and we'll continue troubleshooting.