You can disable a customer instead of completely removing them from MiX Fleet Manager:
- Click Monitor.
- Under Fleet Admin, click Customers.
- Click on the downward actions arrow located to the right of the relevant customer row.
- Click Disable.
- Select a mandatory reason, e.g. contract ended.
- Click Disable.
You can also disable a customer from within the customer details screen by clicking the status bubble as shown below: