Hibernate JPA cannot fetch new record after immediately saving it(within ms) by non-primary key(email,type) but can fetch by primary key(id)

My system has a patient entity that contains email(string), type(integer) fields, both non primary, not unique and not null fields along with other fields and of course a primary key id. <br><br>
After I save a new patient entity, when I search the entity in the database by jpa query findById it works perfectly fine and it fetches that new entity that was just saved few ms ago.<br>
But when I search the newly saved entity by email and type by jpa query findByEmailAndTypeAndEmailIsNotNull it returns nothing but if I run the very same findByEmailAndTypeAndEmailIsNotNull query after 1 second of saving that new entity then it returns that newly saved entity.<br><br>
Can some one diagnose the problem, is it even related to JPA? or with Database itself?

Edit:

@Transactional
public synchronized Patient addPatient(PatientProfileDto patientProfileDto, Integer facilityId)
        throws ResourceAlreadyExistsException, EntityNotFoundException, ClientException {
    // some code

    performPatientCreationValidations(ownerDto, ownerDemographicDto.getNationality().getId(), Boolean.FALSE, Boolean.FALSE);

    // patient creation

    patientRepository.saveAndFlush(patient);

    // some code to link patient to other entities
}

private void performPatientCreationValidations(...params)
        throws ResourceAlreadyExistsException, ClientException {
    if (patientRepository.findByEmailAndTypeAndEmailIsNotNull(patientDto.getEmail(), PatientType.OWNER.getId()).isPresent()) {
        // throw error
    }
}

If I hit the API 5 times in a row with neglible delay then 2 duplicate patient would get created, however on the last 3 apis hits it will throw error as it should. It should have also thrown the error upon 2nd api hit it receives. Also note the adding of patient is synchronized function so when one api hit is completed saving the patient then another api hit acquires lock on function n go on.

> After I save a new patient entity, when I search the entity in the database by jpa query findById it works perfectly fine

JpaRepository.findById() works fine as it takes the entity from Hibernate's 1st level cache, not from the database, because inserting into the database is usually deferred until necessary, e.g. until your session is flushed. An entity can be fetched from the 1st level cache only by its id.

So you have to either flush the Session manually with JpaRepository.flush(), or use JpaRepository.saveAndFlush() instead of JpaRepository.save() or execute your operations within one transaction. In this case your requests share one session and Hibernate is going to flush its cache as soon as it gets a new query for the same entity.