So my electrician installed a 14-50 today and realized he got the wrong breaker for the brand of panel. So he put a 40amp in for now. What catches my attention is the Tesla is showing 242v 16amp and twelve hours to charge. Is this really just a Breaker issue? I expected 32amp not 16amps until the right breaker is installed tomorrow.
Is the current being limited by the setting on your 17" screen? It is GPS sensitive, so it will remember that setting every time you charge at home (or wherever). Maybe you can raise it above 16 amps on that screen? Press on the battery icon at the top of the screen to check the setting...
The car can't tell what kind of breaker is installed, so by default with a NEMA 14-50 adapter, it would default to 40 amps always. Did you set the amps down manually on the car controls?
Generally 16 amps means you haven't properly inserted the UMC, the pilot pin hasn't engaged and it's at the default setting. Pull it back out and try again. There should be two clicks if you push it in slowly. As other have said the Tesla doesn't know what the breaker is. Once you get the UMC plugged in correctly, set the charge level to 24 amps.
24 Amps would be for a 30 Amp breaker. For a 40 Amp breaker, set the current in the car to 32 Amps (80% of 40 Amps). When you get the correct breaker, put it back to 40 Amps. Good Luck!