facility said he needed to come back because his second dose was diluted with sterile water instead of saline; facility said he needed to come back because his second dose was diluted with sterile water instead of saline; Few symptoms; Firmness in my arm; This is a spontaneous report from a contactable consumer, the patient via Pfizer-sponsored program.  A 64-year-old male patient received second dose of bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, solution for injection, Lot Number: EK8732), dose 2 via an unspecified route of administration in arm left on 27Mar2021 as single dose for COVID-19 immunisation at CCAP and distilled water (Distilled Water [Water]), route of administration, start and stop date, batch/lot number and dose were not reported for an unspecified indication. Medical history included, back pain from an unknown date and unknown if ongoing, Congestive heart failure (cardiac failure congestive) from an unknown date and unknown if ongoing, Cholesterol (blood cholesterol) from an unknown date and unknown if ongoing, Allergy (hypersensitivity) from an unknown date and unknown if ongoing. Concomitant medication(s) included atorvastatin (Atorvastatin) taken for blood cholesterol, start and stop date were not reported; Baby Aspirin (Acetylsalicylic Acid) taken for an unspecified indication, start and stop date were not reported; Alerid (Cetirizine Hydrochloride) taken for hypersensitivity, start and stop date were not reported. Historical Vaccine included first dose of bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, solution for injection, Lot Number: EN6198) dose 1 via an unspecified route of administration in left arm on 06Mar2021 as single dose for COVID-19 immunisation at CCAP. The patient stated facility said he needed to come back because his second dose was diluted with sterile water instead of saline on 27Mar2021, few symptoms; firmness in his arm on 27Mar2021. Dates for they used distilled water instead of solution; have a third shot; need to develop the amount of vaccine that they had given. Caller said Those LOT number are the two LOT# that I received and after the second LOT#, today they called me that they used a distilled water instead of solution. They want him to come back and have a third shot because they said they need to develop the amount of vaccine that they had given. So patient had two questions, Is this activity was recommended by you and the other one was that with the third vaccine you can get too much vaccine and one more question did they called you did the (Facility Name) called you and tell you that they had problem with the vaccine, solution of the vaccine, patient should say. Consumer stated, "They told me 2 weeks, but there is no Expiration dates on the sticker that they put on the card, vaccination card. "There is no other number on the second card I can see except LOT#, it is AVEMLGTHEN619 looks like 8." When probed for the Dose of First and Second Vaccine shots, Consumer stated, "he don't know, the dose they didn't told him they told to show up in (Facility Address) and they just gave the first shot other than that they didn't give any details any paper work, nothing." Consumer stated, "The reason why he got the shot, because they said patient could get immune." No, a few symptoms, but nothing serious. he mean firmness in his arm when they gave him the shots and think that was because they injected that too fast and loaded in the muscle and that happens with both shots. So, and that went after one day. The patient underwent lab tests and procedures which included blood cholesterol: unknown results (Cholesterol test and that was month ago). The outcome of events was unknown.  No follow-up attempts are needed. Information about lot/batch number cannot be obtained.  Follow-up (07Apr2021): New information received in response to this follow-up spontaneous report from a contactable consumer. This 64-year-old consumer (Patient) reported that: adverse event and clinical information  Follow up activities closed: No follow up attempt are made.