CDC (Centers for Disease Control) Guidelines for proper storage and handling of Pfizer Purple Cap Covid-19 Vaccines (PPCCV) were created in 2020 and adapted in 2021. Both versions of the guidelines state PPCCV can be stored between 2°C and 8°C (36°F and 46°F) for up to 1 month or in the freezer between -25°C and -15°C (-13°F to 5°F) for up to 2 weeks before dilution, the only two storage systems in our office.    Our clinic placed an order for PPPCCV on 11/3/21 through the Immunization System, vials of PPCCV sent in this order are identified by Lot number FD0809. I am unaware when the shipment was received at the Clinic, I was not a staff member until Nov 30, 2021, however, a  CDC (Centers for Disease Control) Guidelines for proper storage and handling of Pfizer Purple Cap Covid-19 Vaccines (PPCCV) were created in 2020 and adapted in 2021. Both versions of the guidelines state PPCCV can be stored between 2°C and 8°C (36°F and 46°F) for up to 1 month or in the freezer between -25°C and -15°C (-13°F to 5°F) for up to 2 weeks before dilution, the only two storage systems in our office.    Our clinic placed an order for PPPCCV on 11/3/21 through the Immunization System, vials of PPCCV sent in this order are identified by Lot number FD0809. I am unaware when the shipment was received at the Clinic, I was not a staff member until Nov 30, 2021, however a patient's chart indicates they received a PPCCV with lot# FD0809 on 11/11/2021, this indicates the clinic received the shipment between 11/3/21 and 11/9/21.    The PPCCV was stored in the clinic's freezer. Reviewing the temperature logs, the freezer's temperature ranged from-38.7°F to 13.7°F with an average temperature of -22.3 °F while this shipment was stored. Based on the CDC guidelines for storing PPCCV in this temperature range, Lot# FD0809 of PPCCV needed to be disposed of on 11/23/21 at the latest, 14 days (2 weeks) after the last possible day this lot entered our freezer. Members in the clinic failed to safely store the PPCCV in accordance with the shipping and handling protocols and failed to quarantine and dispose of the vaccine properly. Vials from this lot continued to be used to vaccinated patients until 2/11/22, more than 3 months after the date in which the vials should have been disposed of if the vaccines were initially stored properly.      This issue came to my attention on 2/11/22 while I was completing my training when I reviewed the Clinic's shipments and found the PPCCV Lot# FD0809 approved and shipped on 11/3/2021 to be the last shipment of PPCCV made to the clinic. I notified the front desk receptionist, to cancel any future PPCCV Related appointments, I quarantine the expired vaccines. I notified Dr.  and the office manager, about the issues and began to work with PH and Pfizer professionals and created a Case #. I contacted our Electronic Health Records team to help generate a list of all the patients who received a vaccination from this lot. I request information on how to proceed, do patients need to be revaccinated? How should we advise our affected patients?   Our Clinic is reevaluating our procedures and making changes in order to ensure this does not happen again. This is includes making changes how we note when vaccines are received and noting when the dosages expire to ensure this does not occur again.