NCM - 10.1.x
The above issue may be seen for the following reasons:
Smarts NCM has an option to use an alias column rather than device name. This column can be used to give the device an alias to identify the device.
If using the alias column does not deliver the desired result, the device must be rediscovered using SNMP or updated via a config pull including device identity. Ensure that naming update is set to "Always", see image: