Cannot edit posts; “post failed”

I recently became engaged and Facebook automatically chose some photos to slap on the post. I wanted to choose my own and went into edit the post, deleted those photos and added my own, clicked save, and I get a “post failed” notification. This is troublesome as I want the post to show the photos we have chosen to announce with. I have tried closing and reopening the app, restarting my phone, and using both wireless and data to make these changes. PLEASE fix this issue, it’s not exactly like I can un-announce our engagement?

TyanahG about Facebook, v164.0