No adverse event; Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna; Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna; Dose 1 of Moderna monovalent dose on 02-Mar-2022 and Dose 2of Moderna monovalent dose on 27-Oct-2022; This spontaneous case was reported by a consumer and describes the occurrence of INTERCHANGE OF VACCINE PRODUCTS (Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna), COVID-19 IMMUNISATION (Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna), INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (Dose 1 of Moderna monovalent dose on 02-Mar-2022 and Dose 2of Moderna monovalent dose on 27-Oct-2022) and NO ADVERSE EVENT (No adverse event) in an 85-year-old male patient who received mRNA-1273 (Spikevax) for COVID-19 immunisation.    Co-suspect product included non-company product COVID-19 VACCINE PROT. SUBUNIT (NVX COV 2373) (NUVAXOVID) for COVID-19 immunisation.    No Medical History information was reported.   On 02-Mar-2022, the patient received first dose of mRNA-1273 (Spikevax) (unknown route) 1 dosage form. On 27-Oct-2022, received third dose of mRNA-1273 (Spikevax) (unknown route) dosage was changed to 1 dosage form. On 27-Oct-2022, the patient received second dose of COVID-19 VACCINE PROT. SUBUNIT (NVX COV 2373) (NUVAXOVID) (Intramuscular) 1 dosage form. On 27-Oct-2022, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna), COVID-19 IMMUNISATION (Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna) and INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (Dose 1 of Moderna monovalent dose on 02-Mar-2022 and Dose 2of Moderna monovalent dose on 27-Oct-2022). On an unknown date, the patient experienced NO ADVERSE EVENT (No adverse event). At the time of the report, INTERCHANGE OF VACCINE PRODUCTS (Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna), COVID-19 IMMUNISATION (Dose 1 Moderna vaccine, Dose 2 Novavax COVID-19 Vaccine , Dose 3 Moderna), INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (Dose 1 of Moderna monovalent dose on 02-Mar-2022 and Dose 2of Moderna monovalent dose on 27-Oct-2022) and NO ADVERSE EVENT (No adverse event) outcome was unknown.            No concomitant medications were reported.  It was reported that, the patient received first dose of Moderna vaccine on 02-Mar-2022. Later, patient was administered a Bivalent vaccine instead of his required 2nd dose (Monovalent). This error was discussed, and it was advised of: if a bivalent Moderna vaccine was administered for a primary dose: Repeat the dose immediately (no minimum interval) with a monovalent Moderna vaccine because administration of the bivalent Moderna vaccine would result in a lower-than-authorized primary series dosage. Some experts also suggest delaying the repeat dose for 8 weeks after the invalid dose. After the dose had been repeated, continue with the recommended vaccination schedule (i.e., complete the primary series with a monovalent Moderna vaccine, then administer a bivalent booster dose at least 2 months after completion of the primary series). As per this recommendation, the monovalent dose was administered immediately to the patient on 27-Oct-2022.  No treatment medications were reported.