Patients response: Confusion; the “needle broke off” while they were administering a dose of GARDASIL 9 / 1/2 med went into muscle, 1/2 went out of hub; the “needle broke off” while they were administering a dose of GARDASIL 9; Paatient only received 1/2 dose; This spontaneous report was received from a physician and refers to a patient of a not reported age or gender. The patient’s medical history, concurrent conditions. previous drugs reactions or allergies and concomitant therapies were not reported. On an unknown date, the patient was vaccinated with hpv rl1 6 11 16 18 31 33 45 52 58 vlp vaccine (yeast) (GARDASIL 9) injection, expiration date 10-OCT-2026 (strength, dose description, lot # and route of administration) as prophylaxis. On an unknown date, the needle broke off while they were administering a dose of the vaccine, No additional adverse event was reported. Follow-up information was received from a company representative on 12-DEC-2024. It was confirmed that the products were not available to be returned to the manufacturer. Follow-up information was received from a nurse on 16-JAN-2025. The report concerns to a 17-year-old male patient, his demographics were updated. On 10-DEC-2024, the patient was vaccinated with the third dose of hpv rl1 6 11 16 18 31 33 45 52 58 vlp vaccine (yeast) (GARDASIL 9) via intramuscular in the left deltoid (lot number Y013469 was determined to be a valid number). The prefilled syringe experienced a malfunction, half of the dose went into the muscle, the other half came out of the hub (needle issue and poor quality device used), the patient received only half of dose (accidental underdose). It was reported that patient’s response to the incident was confusion. The outcome of the event was not reported. The causal relationship between the events and the suspect vaccine was not provided.