Connect site to social media

I need this site to push new posts to our Facebook page and Twitter profile and show live previews on the homepage. Hook the site so when I publish, the correct page on our Facebook Business page and our Twitter account get the post title, featured image, and the first 50 words. Do the connections in this order: connect the Facebook page first, then the Twitter account, then verify on the homepage that the preview card renders correctly for the latest post. If a permission step fails, stop and tell me which account and which button blocked it.

Before I wire up social feeds, make it obvious to a site reviewer what they will see and why. Put a short note at the top of Settings that states which Facebook page and Twitter handle will be used, surface the sample preview card for the latest post, and flag any missing meta (no featured image, no excerpt) that would make the social card look broken. Call out the specific post IDs that need fixes so an editor can update them quickly.

I just attempted to grant access to our Facebook Business page and the dialog returned an error referencing missing permissions. I am the site owner and admins on the Facebook account. I fear the wrong Facebook Business Manager is linked or the app token is restricted. I cannot see which permission exactly failed from the dialog. What is the likely cause and the step-by-step next move to diagnose and fix the permission mismatch so I can finish the connection?

Every few months the Facebook and Twitter connections break and I waste an hour reconnecting them. I lose time finding which personal account the token used and reauthorizing. Where am I most likely dropping the ball on setup and what habit should I change so the connections stay stable and handoffs are clean between editors and me?