iPHone key unlocks car, turns on, but car won't go without plastic key.

[SciFriGuy]

After working well for months, my car suddenly refused to be put in drive after having unlocked the car with my iphone key. Entered the car, stepped on brake. Seat went through adjustments, screen came on and all looked like it was working. Except I couldn't put the car in reverse or drive. Only after putting the plastic card key on it's spot did the car go into reverse/drive.
Any suggestions why?

 

[BluestarE3]

Did you happen to lift your butt off the seat?

 

[eli_]

Look under Bluetooth devices on your phone and make sure it sees the car's "console" Bluetooth beacon. There should be 4 devices that are a random string of letters and numbers, and the console antenna should end with a letter "C". If it's not there try toggling Bluetooth on the phone.