SUSPECTED CLINICAL VACCINATION FAILURE; SUSPECTED COVID-19 INFECTION (COVID REBOUND); This spontaneous report received from a consumer via other manufacturer (Pfizer) concerned a 37 year old female. The patient's height, and weight were not reported. The patient's concurrent conditions included: fibromyalgia, and drug allergy, and other pre-existing medical conditions included: Patient was not pregnant at time of vaccination. The patient previously received covid-19 vaccine ad26.cov2.s (dose number in series 1) (suspension for injection, route of admin not reported, batch number: unknown, expiry : unknown) dose not reported, 1 total, administered on an unspecified date for prophylactic vaccination.  It was unknown whether patient had any adverse events following vaccination with first dose of covid-19 vaccine ad26. cov2.s (dose number in series 1).  The patient received covid-19 vaccine ad26. cov2. s (dose number in series 2) (suspension for injection, route of admin not reported batch number: unknown, expiry: unknown) dose were not reported, 1 total, administered on an unspecified date for prophylactic vaccination. The batch number was not reported and has been requested. Concomitant medications included hydroxyzine embonate, lifitegrast, pantoprazole sodium sesquihydrate, salbutamol and sertraline hydrochloride used for unknown indication. On 29-MAY-2022, the patient experienced suspected clinical vaccination failure (suspected covid-19 with symptoms) (dose number in series 2). The patient additionally received non-company suspect vaccine Moderna covid-19 vaccine (elasomeran) (dose number in series 3) (form of admin and route of admin were not reported, batch number: unknown, expiry: unknown) dose was not reported administered at left arm on an unspecified date for prophylactic vaccination.  On 29-MAY-2022, the patient tested positive for covid-19 infection (dose number in series 3). On the same day, patient took Paxlovid (nirmatrelvir and ritonavir) (form of admin, route of admin, and batch number were not reported) dose was not reported administered for covid-19 treatment. Patient received last dose of Paxlovid on 03-JUN-2022.  On 04-JUN-2022, Laboratory data included: COVID-19 antigen test Negative. On 13-JUN-2022, the patient experienced recurring symptoms of covid-19 (covid rebound) and Laboratory data included: COVID-19 antigen test Positive (dose number in series 3). The action taken with covid-19 vaccine ad26.cov2.s, and elasomeran was not applicable and action taken with Paxlovid was drug discontinued. The patient had not recovered from suspected covid-19 infection (covid rebound), and the outcome of suspected clinical vaccination failure was not reported. This report was serious (Other Medically Important Condition). This report was associated with product quality complaint.; Sender's Comments: V0: 20220645128 -Covid-19 vaccine ad26.cov2.s -SUSPECTED CLINICAL VACCINATION FAILURE. The event(s) has an unknown/unclear temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: SPECIAL SITUATIONS. Therefore, this event(s) is considered not related.