Facebook Social Feed API error code

Our Social Feed App relies heavily on the individual social networks' APIs. For our Facebook Feed, we use the Facebook Graph API. 

What is an API?

An API is a way for one company to get data from another company through an authorized connection. Every company offering an API will have documentation available that tells a developer how they can get the data they need via the API. 

For example, Facebook's complete API documentation lives here. For our Social Feed, we ask Facebook to send us posts from public Pages and Groups. Facebook sends the data matching our query to our servers, making it possible for us to display your posts in your Facebook Social Feed.

What is an API error code?

Apps using APIs are dependent on that API giving us the requested information in order to make your App work. Any changes that Facebook makes to its API can potentially affect how our Facebook Feed works. If the Facebook API is down, this may also mean that new requests cannot be handled until the API is back up.

Additionally, there are a few common API error codes that you may encounter in your Facebook Social Feed which can give you hints about what went wrong:

• API Error Code 400: This typically means that our query for getting data from Facebook is not properly working. Please contact us ASAP when you see this error as it might require us to make updates to our code.
• "Nothing founds for [query]": If you see this API error, Facebook is telling us that a public Page or Group does not exist for the query you entered. Please check to make sure the source you are trying to connect is set to fully public, has no audience restrictions on it, and contains public posts.