Issue

The sum of users in a report does not add up to the total in Google Analytics.

Environment

Google Analytics UI

Resolution

You should not add the number of users in Google Analytics and the reason is a single user can have multiple sessions (i.e. a user can log in at various times). Nevertheless, every time they visit your site, even if it is the same user, they would be counted as a new user.  For more information on this metric please read the following article https://help.analyticsedge.com/article/misunderstood-metrics-users/ 

Cause

This usually happens when you are in the process of verifying the data synced to your warehouse with what you see on the Google Analytics UI.