2020 T880 NavPlus antenna question

i have a new T880 with Nav Plus. i took it back to the dealer to have the backup camera installed because it was not on the truck when i got it two months ago.
took them 4 days to put it in.
got the truck back Wednesday night.
yesterday i needed the navigation and it did not work. showing location as where i was the last time i used it Thursday morning and not showing any satellite reception.
so i am thinking they did not plug the GPS antenna back in.
does anyone know where it is so i can do it myself?
i went to the dealer this morning to ask and they told me i will have to bring the truck back and leave it with then for a few days s they can get a representative of the navigation company there to look at it, which is total BS.
it is bad enough they charged $931 and took 4 days to put the camera in, i also had to put the radio back in the dash after it fell out because they never locked it in the dash. plus not plugging the GPS antenna back in.
i would rather do it myself and not let them touch the truck again

 

no idea. i have only had the truck for two months and nothing appears to be out of place. but i do not know what i am looking at with this unit, because i have never worked on one with a radio AND 7 inch android device for display screen.

 

i should rephrase that.
this truck does not have a "GPS"
it has a radio in the dash, and a 7 inch android touchscreen device above the radio in the dash that is the main display screen for most functions in the truck. the navigation is an app in the android device.