In alfresco process service , I have designed process in a result of that when the process gets completed, It will update the property of a document.This document is selected in between the business process.
When business process reach at below task , it is not updating the property and it is throwing an exception which is attached in a file.
So the error is originating from com.activiti.service.idm.AlfrescoEndpointServiceImpl.getById(AlfrescoEndpointServiceImpl.java:38) and is that "The given id must not be null!" The alfresco endpoint should contain a tenant, repositoryUrl etc. - it's how APS knows how to reach the content repository. It looks like your APS installation or your process is missing some configuration. I take it you set up a repository and so on as per https://community.alfresco.com/community/bpm/blog/2016/12/01/activiti-enterprise-developer-series-st... ?
If you're an enterprise customer you have the option to raise an issue through the official support channel. I am keen to help but I should be clear that this isn't the official enterprise support channel.