Sore arm; The needle went into the arm and she pulled out the needle and continued to squirt and this went into the crease of my elbow; Vaccine ran down arm; Only one-fifth was administered; They don't know if I even go half of the dose; The vaccine ran down my arm and puddled in my arm/Vaccine leaked out of her arm; This spontaneous case was reported by a consumer and describes the occurrence of UNDERDOSE (They don't know if I even go half of the dose), DEVICE CONNECTION ISSUE (The vaccine ran down my arm and puddled in my arm/Vaccine leaked out of her arm), PAIN IN EXTREMITY (Sore arm), ACCIDENTAL EXPOSURE TO PRODUCT (Vaccine ran down arm) and INCORRECT DOSE ADMINISTERED (Only one-fifth was administered) in an 88-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 023M20A and 042L20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No medical history was reported by the patient.  Concomitant products included MEMANTINE, PRIMIDONE, ATORVASTATIN, FAMOTIDINE, ACETYLSALICYLIC ACID (BABY ASPIRIN), VITAMIN E NOS (VITAMIN E [VITAMIN E NOS]) and MULTIVITAMINS [VITAMINS NOS] for an unknown indication.   On 28-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 25-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 25-Feb-2021, the patient experienced UNDERDOSE (They don't know if I even go half of the dose), DEVICE CONNECTION ISSUE (The vaccine ran down my arm and puddled in my arm/Vaccine leaked out of her arm), ACCIDENTAL EXPOSURE TO PRODUCT (Vaccine ran down arm) and INCORRECT DOSE ADMINISTERED (Only one-fifth was administered). On an unknown date, the patient experienced PAIN IN EXTREMITY (Sore arm) and PRODUCT ADMINISTERED AT INAPPROPRIATE SITE (The needle went into the arm and she pulled out the needle and continued to squirt and this went into the crease of my elbow). At the time of the report, UNDERDOSE (They don't know if I even go half of the dose), DEVICE CONNECTION ISSUE (The vaccine ran down my arm and puddled in my arm/Vaccine leaked out of her arm), ACCIDENTAL EXPOSURE TO PRODUCT (Vaccine ran down arm) and INCORRECT DOSE ADMINISTERED (Only one-fifth was administered) had resolved and PAIN IN EXTREMITY (Sore arm) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 10-Mar-2021, SARS-CoV-2 test: negative (Negative) Normal.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Patient reported not taking any medication prior to vaccination in follow up 30-APR-2021.   This case was linked to MOD-2021-142294 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 29-Apr-2021: Event details of first and second dose were added. On 13-May-2021: Lab data Covid test negative on 10-MAR-2021 was added. On 17-May-2021: Follow up received on 17-MAY-2021 does not contain any new information. On 18-May-2021: Expiration date of dose 1 and dose 2 were added. Indication of primodone was added. On 18-May-2021: Follow up received on 18-MAY-2021 does not contain any new information. On 19-May-2021: requesting phone call On 19-May-2021: Email, unable to fill out forms, requesting phone call. On 20-May-2021: Patient unable to fill the form.; Sender's Comments: This report refers to a case of underdose and device connection issue for mRNA-1273, lot # 023M20A with no associated AEs.