patient was given 6x the standard dose which is more than the recommended/Patient received a far higher dose then expected/it was undiluted; Patient received a far higher dose then expected/it was undiluted; tingling sensations in the arm; tiredness; arms soreness; numbing/it's numb; Sleepy; Lethargic; Weak; feels funny; This is a spontaneous report received from a contactable physician. A 20-years-old female patient received BNT162B2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Formulation: Solution for injection, Batch/Lot number and Expiry date was not reported), via an unspecified route of administration on 07Oct2021 as a dose 2, single for COVID-19 immunization. The patient's medical history and concomitant medications were not reported. Historical vaccine included BNT162B2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Formulation: Solution for injection, Batch/Lot number and Expiry date was not reported), via an unspecified route of administration on an unspecified date as a dose 1, single for COVID-19 immunization. Enquired, the physician stated that, their office gave a 2nd dose of an undiluted Pfizer-BioNTech Covid-19 Vaccine to a 20-year-old female patient. Stated that, the patient was given 6x the standard dose which was more than the recommended. Stated that, the patient received a far higher dose then expected/it was undiluted on 07Oct2021. Currently, on an unspecified date in Oct2021, the patient experienced tiredness, arms soreness and numbing and tingling sensations in the arm. Stated that, the healthcare professional wanted to know what they should do next. Response included was provided disclaimer and responded, Inadvertent Administration of Higher than the 0.3 mL recommended dose. Stated that, Practice Administrator, on behalf of the physician, to send her the questionnaire to her email for completion. The reporter also confirmed that, AERs ### and ### are for the same patient and that the verbatim for the overdose event is as documented in AER ###. Reporter did not provide the dose number for the events. The reporter stated that, once she receives the questionnaire via email, they will complete it. The reporter stated that, he was called about the Pfizer Covid Vaccine. Stated that, he has a question and needed some guidance, they were giving the vaccine out yesterday and 1 patient received a dose, the vaccine was given before it was diluted, in other words it was undiluted and the patient received a far higher dose than expected. The patient was sleepy lethargic weak, her arm hurts and it's numb, she told her mom she feels funny. The reporter stated that, she was looking for some guidance. The reporter stated that, this was the number the rep gave him. Stated that, he was trying to submit all the paperwork to report this. The reporter declined to complete a safety report at this time. Stated that, he just got called overhead by a different physician and has to go at this time. The outcome of the events for tingling sensations in the arm, tiredness, arms soreness, numbing/it's numb was not recovered while for the other events was unknown.  This is a follow-up report combining information from duplicate reports [202101342052] and [202101343055]. The current and all subsequent information will be reported under manufacturer report number [202101342052].   The lot number for the vaccine, [BNT162B2], was not provided and will be requested during follow up. Sender's Comments: As there is limited information in the case provided, the causal association between the events overdose, product preparation error and the suspect drug BNT162B2 cannot be excluded. The case will be reassessed once new information is available.