Doubleclick on pin 2 [ M11 ] and in the dialog on button [Edit pin name]:
(Image 2: Change pin name)
Enter e.g. GND to the "Content" line. Confirm both dialogs by [OK]. The name appears and needs to be adjusted:
(Image3: Name to pin genereated)
You can displace the pin now by drag and drop [ M1h ]. When selecting it by the mouse consider to only move the name. The highlighted pin always highlights its name too. The highlighted name does not highlight the pin. Use [Esc] in order to give up the selection. Now click [ M1H ] on the name to displace it:
(Image 4: Done)
In the same way we can add the text "+9V" to pin number 1. To get rid of a name, you simply would highlight it and then delete it using key [Del].
(Image 1: Connector with a pin name missing
(Image 2: Change pin name)
(Image3: Name to pin genereated)
(Image 4: Done)