Marguerite
Sometimes doing an uninstall & re-install of the game app &/or Facebook can help.
But make sure....before you do any uninstalling....that your player ID number & game progress is registered with either your email address or Facebook account.
There are some very useful discussion threads in relation to friends & Facebook....you can check these out through the links below.
https://forum.pixelfederation.com/diggysadventure/d/170729-facebook-friendlist-synchronization-keeping-diggy-friends-seperate-etc
https://forum.pixelfederation.com/diggysadventure/d/169427-privacy-settings-on-facebook-and-their-effects
https://forum.pixelfederation.com/diggysadventure/d/173356-cannot-add-friends/2
https://forum.pixelfederation.com/diggysadventure/d/187290-what-is-daf2/2
https://forum.pixelfederation.com/diggysadventure/d/186940-how-to-add-friends/23
There is also a Wiki page with a list of Facebook groups.
https://wiki.diggysadventure.com/index.php?title=Facebook_Groups
Please note that Friends, Neighbors, Windmills, God Children & Gifting System are NOT available if playing through Android or Apple mobile game application.
To access these features of Diggys Adventure, you MUST play through the Portal or Facebook.
However you MUST also have your game connected to a Facebook account.
There are also some very useful pages on Wiki regarding Windmills, God Children, Neighbors & Gifting System....you can check these out through the links below.
https://wiki.diggysadventure.com/index.php?title=Neighbors
https://wiki.diggysadventure.com/index.php?title=Rewards
https://wiki.diggysadventure.com/index.php?title=Gifting_System
https://wiki.diggysadventure.com/index.php?title=Energy#Windmills
https://wiki.diggysadventure.com/index.php?title=Energy#God.27s_Children