Unbalanced Journal Legal Error - Unable to Post Invoice

SOLVED

We are using X3 version 11.  I have been invoicing and posting for the same customer without issue until today.  Now I am unable to post any new invoices.  Seems to be with just this customer though.  Error message just says "Unbalanced Journal Legal    Rollback following error in transaction".  Note:  These are direct invoices and are not tied to actual shipments.  Any ideas on how I can fix this and how it occurred to prevent it from happening again?  Any help is appreciated!  Thanks.