First, try reloading the page to see if that helps it start syncing again.
Second, if reload doesn’t work, back up what you have written using export to Word from the book action menu.
If you’ve written a lot while it has not been syncing and don’t want to have to copy-paste it back in from your Word backup, you can go into Preferences and choose Export Database (scroll to the very bottom under "Data Management").
Then, send the file you receive to Jacob via chat or email ([email protected]), and he will be able to import your data for you.
After you’ve backed up your data, you can use "Sign Out" from Dabble’s account menu to delete your local database on your computer.
Then when you sign back in you will have a fresh sync from the server.