Login to LandingAdmin as a user who has access (Configuration User, Group Editor, Group Owner)
Go to the desired user details page to update their profile.
At the bottom of the page, click the Add Group and a pop-up window will appear.
Search for the desired group(s) you wish to add and click on the group(s) you wish to add.
Click on + Add Groups to User to finish adding the group(s) to the user.
Repeat the steps above for additional groups you wish to add.
Note: You can only select groups within the same page to add to the user. If you have groups on different pages, you will need to repeat the steps for each additional page.