Nodeum creates an Administrator User, by default this user has the ID : 1000. This ID is created automatically when the packages are deployed.
Before installation :
If you already has a user with the same ID, you will have two choices : either you change your existing user to another ID or you have to assign another ID for Nodeum Administrator User.
You can change your existing User's ID :
If you have already users with this ID, you have to change it in using this command :
"username" is the username
You can't change your existing User's ID :
To solve this incompatibility, you need to change this variable before the installation.
These settings are defined in the vars/main.yml file of Ansible package.
You have to replace the number uid : "1000" by another available ID in your system.
Be careful, don't change the gid ID value