The blower for the a/c and heater, defrost stopped working. would work sometimes, now doesn’t work at all
Check the fuse.
If that’s good, check if the blower’s getting power.
If it’s not, the resistor group probably failed.
Do you have high speed? The reason I’m asking is that high speed bypasses the resistors.
Turn the ignition switch on. Set the blower speed to high. Reach under the passenger side of the dash and tap on the blower motor with the handle of a screwdriver. If the blower motor starts working the blower motor requires replacement.
Tester