3 children were given booster doses of the orange cap that were not diluted; 3 children were given booster doses of the orange cap that were not appropriately diluted; Fever; Achiness; More robust immune response; This is a spontaneous report received from contactable reporter(s) (Nurse and Physician) from medical information team.  A 5-year-old male patient received BNT162b2 (BNT162B2), on 26Aug2022 at 15:03 as dose 3 (orange cap; booster), 0.2 ml single (Lot number: FL8094, Expiration Date: 31Aug2022) at the age of 5 years intramuscular, in left arm for covid-19 immunisation. The patient's relevant medical history included: "Asthma", start date: 14Sep2019 (ongoing), notes: Albuterol prn; "Wheezing", start date: 14Sep2019 (ongoing), notes: Albuterol prn. There were no concomitant medications. Vaccination history included: BNT162b2 (DOSE 1, SINGLE, Time of administration: 16:08, Lot number: FK5618, Anatomical site of injection: Left Arm, Route of administration: Intramuscular), administration date: 14Dec2021, when the patient was 5-year-old, for COVID-19 immunization; BNT162b2 (DOSE 2, SINGLE, Time of administration: 16:20, Lot number: FK5618, Anatomical site of injection: Left Arm, Route of administration: Intramuscular), administration date: 04Jan2022, when the patient was 5-year-old, for COVID-19 immunization. The following information was reported: IMMUNISATION REACTION (non-serious) with onset 2022, outcome "unknown", described as "More robust immune response"; PAIN (non-serious) with onset 26Aug2022, outcome "recovered", described as "Achiness"; PYREXIA (non-serious) with onset 26Aug2022, outcome "recovered", described as "Fever"; PRODUCT PREPARATION ERROR (non-serious) with onset 26Aug2022 at 15:03, outcome "unknown", described as "3 children were given booster doses of the orange cap that were not appropriately diluted"; OVERDOSE (non-serious) with onset 26Aug2022 at 15:03, outcome "unknown", described as "3 children were given booster doses of the orange cap that were not diluted". Therapeutic measures were not taken as a result of product preparation error, overdose. Therapeutic measures were taken as a result of pyrexia, pain, immunisation reaction.  Additional information: The patient did not receive any prior vaccination within 4 weeks. The patient did not receive any concomitant drugs. No staff available for help, other vaccines being used were pre-diluted. It led to more robust immune response. The events fever and achiness started in 1-2 hrs. The patient did not have any relevant tests or tests for thromboembolic events with thrombocytopenia. The event did not require the initiation of new medication/other treatment/ procedure. The patient was treated at home with over the counter (OTC) medications. The adverse event outcome was also reported as recovered with sequelae. The patient provided information regarding the reported adverse event(s) with the use of the product. The Pfizer product had a causal effect to the adverse event. This report is not serious.  Follow-Up (06Sep2022): Follow-up attempts are completed. No further information is expected.  Follow-up (17Oct2022): This is a spontaneous follow-up report from a contactable Physician. This Physician reported in response to HCP letter sent to physician via follow-up letter. Updated information included: Reporter details updated, historical vaccines (time, route, anatomical site and lot number updated), relevant medical history added, suspect drug (start and stop time updated), new events added, event details (onset time updated for product preparation error and overdose). Additional information updated. Sender's Comments: Linked Report(s): PFIZER INC-202201099254 Same drug/event, different patient.