The fact that a second Device is getting created could occur if the first Device was Deleted from the Network Scan results. Having that said, make sure to not delete any items from the Network Scan results unless you wish to recreate all of your Devices.
When a second Device is created, you can move its Monitors to the original Device by using the steps in the following article:
Hope this helps.
Chris Foley | Support Specialist
SolarWinds | IT Management, Inspired By You
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