2009 Nissan Sentra - TPMS issue

Had new valve stem extender placed on tire as old one cracked. Now low tire pressure light has come on, but all tires are ok. What is happening?

Transmitter in the valve stem is probably worn out. The life of these are just a few years. Probably coincidence that it failed when you added extender. A tire place can check to see which tires are transmitting and which ones are not.