Left swollen axillary lymph node; Flucelvax Quadrivalent and Pfizer-BioNTech COVID-19 Vaccine, Bivalent were administered on the same date, in the same arm; This spontaneous case was retrieved on 14-Nov-2022 from Vaccine Adverse Event Reporting System (VAERS) (reference number: 2492129-1), reported by other healthcare professional, and concerned a 54-year-old, female patient.  The patient's medical history was not reported. The patient's concomitant medications included Colace (docusate sodium), famotidine, UMCKA A (pelargonium sidoides), vitamin D3 (colecalciferol) and unspecified probiotics, all used for unreported indications. The patient's historical vaccines included first three doses of COVID-19 vaccine (brand not specified), received on unspecified dates, all for COVID-19 vaccination. The patient had no known allergies. The patient did not receive any other vaccine within four weeks prior to vaccination. The patient was not diagnosed with Covid-19 prior to vaccination. The patient was not pregnant.  On 21-Oct-2022, at 18:45, the patient was vaccinated with non-company, co-suspect Pfizer-BioNTech COVID-19 Vaccine, Bivalent (tozinameran, riltozinameran; dose: reported as '4', anatomical location: left arm, route of administration: not reported) for Covid-19 immunisation. The batch number reported was GJ6665.  It was reported that on the same date, the patient was vaccinated with influenza vaccine (brand not specified; anatomical location: left arm, dose and route of administration: not reported) for immunisation (explicitly coded as 'Product administration error'). The batch number reported was 942415. The reported batch number was identified by Seqirus to be linked to suspect product Flucelvax Quadrivalent (influenza vaccine inact sag 4v) instead of reported suspect product influenza vaccine. Based on the reported batch number, the suspect product was changed to Flucelvax Quadrivalent.  On 23-Oct-2022, two days after receiving Flucelvax Quadrivalent and non-company, co-suspect Pfizer-BioNTech COVID-19 Vaccine, Bivalent, the patient experienced left swollen axillary lymph node. Therapeutic measures were not taken. The patient had not been tested for Covid-19, since the vaccination.  At the time of initial reporting, the patient was recovering from the event.  The reporter did not provide a causality assessment.  The case was assessed as non-serious.  Company comment: A 54-year-old patient was vaccinated with Flucelvax Quadrivalent and non-company, co-suspect Pfizer-BioNTech COVID-19. Two days after vaccination, the patient experienced left swollen axillary lymph node. Although confounded by co-suspect vaccine, causal role of the suspect vaccine is assessed as possibly related due to suggestive time relationship. Both vaccines were given on the same day, in the same arm. Product administration error is assessed as not related as per company specific guidelines.; Sender's Comments: A 54-year-old patient was vaccinated with Flucelvax Quadrivalent and non-company, co-suspect Pfizer-BioNTech COVID-19. Two days after vaccination, the patient experienced left swollen axillary lymph node. Although confounded by co-suspect vaccine, causal role of the suspect vaccine is assessed as possibly related due to suggestive time relationship. Both vaccines were given on the same day, in the same arm. Product administration error is assessed as not related as per company specific guidelines.