Cant update form with getting following error [t_533547000000037895_PIDX] Exception occured while inserting rows

Cant update form with getting following error [t_533547000000037895_PIDX] Exception occured while inserting rows

I keep getting this error when trying to update a form. Im using a drop down list.  Ive read this issue occuring and made certian there were no fields that did not allow dups and no required fields in the form. 
 
[t_533547000000037895_PIDX] Exception occured while inserting rows
Failed to update data.