Shared Library Error - "Request Entity Too Large"

There is a shared template file for the case managers within the hospital system. However, whenever someone chooses a template to send for signature, they get this error message:

Request Entity Too Large

The requested resource
/api/rest/v6/agreements
does not allow request data with POST requests, or the amount of data provided in the request exceeds the capacity limit.

Apache Server at na2.documents.adobe.com Port 443 

What is the fix for this issue?