Um. It's a tire on a wheel, with a standard Schraeder valve, just like any standard bicycle or any other car. Your hand-held bicycle pump, upright bicycle pump, the $25 Autozone Special air pump that plugs into 12V (there's an outlet in the arm rest), or an air pump, pay or not, at any gas station/service station/tire shop/etc. will work. Nothing special, and you don't need to use mobile service unless you really feel the need.
If you decide to use Tesla, go to the App, select Service, then tap on Request Service. Then you can select Tires & Wheels. There's not an entry for low air, so I'd guess you'd select "Other - Tires & Wheels", then write up your business about low air pressure.
Thing is.. There is one service Tesla provides in this regard that you may have heard of, and that's if you get a flat. This actually happened to me one evening, driving around Mountainside. Going downhill on a road sans curb, discovered that a homeowner had allowed the stones lining their property had allowed some of them to get into the street, where one made close contact with the front right. This tore a hole in the sidewall, set off the usual low air pressure alarms, and I limped to a parking spot on a nearby residential street, at which point the tire lost all air.
This is where the "Swap your tire" item in the Service menu in the app comes into play. Did that, Tesla has a service where a fellow in a truck/car shows up and swaps your wheel for a spare in his truck, then sends you on your way. If the wheel/tire is repairable, Tesla will do that. In my case, the fellow showed up in a half hour. The tire needed replacing, so I had one drop-shipped to the SC, then showed up at the SC with the car and they swapped the repaired wheel with the loaner. I got charged for tire disposal, remounting, and balancing.
The, "Swap your tire" feature is there, pretty much, to handle the case when (a) you've got a flat, (b) you've got a spare and jack, and (c) you put the spare on. You then throw the bad wheel in the trunk and go looking for a repair place to get it fixed. Since Teslas don't have spares, that's why the tire swap guy.
If you're out in the boonies and out of range of the tire swap service, the alternative is a flat-bed tow truck to some repair place. AAA or the equivalent is good for that kind of thing.
On the other hand, since you've got what appears to be a slow leak, the alternate plan is to put some air in your tire and make your way over to a Mavis Tire, Costco, or your friendly local service station and mechanic, if you've got one. For anywhere from free to $50 or so, they'll pop the wheel off your car, inspect it, dunk it in a tank of water that they keep for the purpose, and locate the leak. If it's repairable, they'll fix it in the spot. If not, well, there's a new tire in your future.
lol To Funny 
