Unable to send for signature, error message

Hello, 

I am unable to send request for signatures.  I have been doing so for a few years, but no longer have the ability.  I can perform other tasks (i.e. edit, organize pages), but when I "request signature" I receive the following message.  "You have logged out.  An error occurred.  Please try signing out, and signing in again"....with a blue Sign in button.  If I click on the blue link, the same message flashes.  If I open up another pdf, it shows I am signed in.  I have signed out and closed all pdfs.  I have cleaned cookies on my computer.  I have rebooted the computer.   All several times, to no avail.  

How can this be fixed?

Thank you.