Nintex workflow is not identifying user profile with full name some times.

[#1]

SharePoint 2013 Nintex workflow is not identifying valid user profile with full name some times. same step executed successfully for hundreds of records.

[andrewg]

Is it possible to provide an example, may with screen shots if you can? I'm wondering what values you are trying to compare within which actions. Are you comparing true User Profile Service, or the user context information such as the current user display name.

[#3]

We have identified as issue with user profile services not related with Nintex.