The bulb could look good, but be bad. If you have a multimeter, check resistance. While you're at it, check for voltage at the bulb socket terminals while a helper applies the brakes.

If you don't have a multimenter, buy a new bulb, it's cheaper than a meter.

Filaments can break, dangle around a work one day and not the next. The break can be nearly invisible to the naked eye.

For the parking lights, first be sure that you have the correct bulbs. Parking lights by themselves are only one filament. Combination parking and turn signal, or parking and brake will have two filaments.

Sockets can loosen, or break, and an open contact means no current, so no lamp function.

Best Regards,
Jim