pdf expert iPad Account configuration error. Re-add account

It seams pdf expert and dropbox still have glitches. I have deleted both, reloaded both but am still having problems with pdf expert sync with dropbox. for some reason it won't send current information to dropbox or for months now when i delete a file on my desktop the iPad pdf expert keeps adding it back but with zero bytes. Right now half way through the day the iPad pdf expert just stops sync with desktop and gives me an error. How do I stop this?