How to add a sensor type in Sensor list

How to add a sensor type in Sensor list

Hi,
I have two sensor devices in my account - one with Dragino TrackerD connector, another with a private connector called "Custom Dragino TrackerD." I see the "Custom Dragino Tracker D" in the Sensor Type dropdown link in the Add Sensor dialog, however, I do not see the "Dragino TrackerD " type there. Please let me know what I need to do to make that type available in that sensor type.

Here is a screenshot for your reference