possibly underage; This non-serious case was reported by a nurse via call center representative and described the occurrence of inappropriate age at vaccine administration in a 5-month-old patient who received Flu Seasonal TIV Quebec (FluLaval 2024-2025 season) for prophylaxis. On 10-DEC-2024, the patient received FluLaval 2024-2025 season. On 10-DEC-2024, an unknown time after receiving FluLaval 2024-2025 season, the patient experienced inappropriate age at vaccine administration (Verbatim: possibly underage). The outcome of the inappropriate age at vaccine administration was unknown. This report is made by GSK without prejudice and does not imply any admission or liability for the incident or its consequences. Additional Information: GSK Receipt Date: 02-JAN-2025 The register nurse stated that they were getting a billing error edit for age on a flu vaccine, Flulaval. The child was 24 weeks and 2 days when administered which led to inappropriate age at vaccine administration. The vaccine was given on 10th December 2024. The reporter did not collect any further information as it was uncertain based on PI if patient was underage as it just stated 6 months and depends on what the definition of 6 months.