Last Updated: 01/11/2018
This issue has now been resolved
Facebook has advised that they are currently aware of an issue which is affecting third party Apps like Sendible's.
This issue means that, in some cases, if you are given admin access to a new Facebook Page, even if you're previously added Facebook Pages as services on Sendible, this new Facebook Page cannot be retrieved by us.
We are closely monitoring this issue and awaiting updates from Facebook.
As a workaround in the meantime, if you give admin access to any affected Facebook Pages to a Facebook Profile that has not previously been used to add services on Sendible, you should be able to add the Facebook Pages as services when logged into that Facebook Profile.