If your vehicle is showing door won't open from the inside, here are the most likely causes and the parts you'll need to fix each one.
If this is a rear door, the child safety switch on the edge of the door may be flipped. This intentionally disables the inside handle to prevent children from opening the door while moving.
The plastic interior door handle has snapped internally or stripped where it connects to the latch cable. The handle will often feel loose or completely floppy when pulled.
The cable or rod connecting the inside handle to the door latch has snapped, or it was accidentally left disconnected after recent work behind the door panel (like replacing a window motor or speaker).
The latch assembly inside the door is jammed, rusted, or internally broken. Even though the handle and cable are pulling correctly, the latch refuses to release from the striker.
The electronic lock actuator is mechanically jammed in the locked position. Because the door cannot physically unlock, pulling the inside handle will not open the door.