You are scanning products in Kelvin and suddenly you get this popup saying "Client permission issue" as shown below here.
The issue is that one or more members on the team don't have permission to work on this client.
You can see what client you are working on (In this case above it is "APEX STUDIO")
You can see what member of the team the issue is about (In this case above it is "Domenica Dorn")
You now have two options "Continue" or "Cancel"
You can click "continue" and ignore this issue and keep working as usual but you will run into this issue later.
You can click "cancel" and fix the issue. You go into Gamma and click "Studio Settings" then you go to "User groups" and add the user(s) to the right client user group or the group "All Clients" as shown below here.
Note: If you don't have permission to edit this you must contact your admin and let he/she handle it.