A prescription of atorvastatin 20 mg is dispensed to a patie…

A prescription of atorvastatin 20 mg is dispensed to a patient who takes the medication home. Prior to taking their first dose, the patient observes the medication looks different than what they have taken in the past. The patient contacts the pharmacy and reads the code on the tablet to the pharmacist. The pharmacist determines that atorvastatin 40 mg was dispensed instead of what was prescribed. Which category of medication error occurred?