A "SIM Not Provisioned" error can occur due to various reasons, like new SIM activation or compatibility issues. Try simple solutions like restarting your phone ...

When you have that, turn off your Android device ... might also have a spot for a MicroSD card and/or another SIM card, so add, remove, or swap any cards as needed. Once the cards are flat ...

If you have one of the compatible Metro by T-Mobile Android phones ... is the modern way of activating a SIM card on a new device, and it will likely replace physical SIM cards.