Trouble watching saved videos on Facebook

Hello armyguardmom,

Welcome to Apple Support Communities. 

We understand that you are not able to play videos on Facebook as expected. We are happy to help.

These steps may help. Please try the steps here: If an app on your iPhone or iPad stops responding, closes unexpectedly, or won’t open - Apple Support

1. "Close and reopen the app
2. Restart your device
3. Check for updates
4. Delete the app, then redownload it"

You can use the steps here to contact the developer of facebook if no resolution: How to contact an app developer - Apple Support

"Contact the developer of an iOS, iPadOS, or watchOS app

1. Open the App Store on your iPhone or iPad.
2. Search for the app, then tap it. If you can't find it, tap the account button  or your photo at the top of the screen, tap Purchased, tap "Not on this [device]," then tap the app.
3. The app's product page appears. Scroll to the Ratings & Reviews section, then tap App Support. If you don't see App Support, make sure that you're signed in with the correct Apple ID."

Let us know if you have further questions.

Take care.