Foreign key constraint @ManyToMany relationship preventing deletion

Question

I've three associated records (Conference, SubmissionRecord, SubmissionAuthorRecord). Every SubmissionRecord has a Conference object and has a List<SubmissionAuthorRecord>.

When I delete a Conference record if the SubmissionRecord is associated with that Conference, it should cascade and delete as well. However, I keep getting a java.sql.SQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`viz`.`submission_record_author_set`, CONSTRAINT `FKgnqq52l26bitkmojk1oiuaki1` FOREIGN KEY (`submission_record_s_id`) REFERENCES `submission_record` (`s_id`)) error message.

The table submission_record_author_set is create automatically and I have no entity that maps to it.

I understand the issue lies in the fact that the submission_record_author_set rows are preventing the SubmissionRecord from being deleted and have tried the @PreRemove method described here (How to remove entity with ManyToMany relationship in JPA (and corresponding join table rows)?) but to no avail. Maybe there's an issue with the ManyToMany annotation? Cause I do not see the equivalent annotation in the SubmissionAuthorRecord either.

@Entity
public class SubmissionRecord {

    @Id
    @GenericGenerator(name = "UseExistingIdOtherwiseGenerateUsingIdentity", strategy = "xyz")
    @GeneratedValue(generator = "UseExistingIdOtherwiseGenerateUsingIdentity")
    @JsonSerialize(using = ToStringSerializer.class)
    @Column(name = "s_id")
    private Long id;

    @Exportable(name = "Submission Id", nameInDB = "s_submission_id")
    @Column(name = "s_submission_id")
    private String submissionId;

    // internal set of authors of the associated
    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JsonIgnore
    private List<SubmissionAuthorRecord> authorSet;

    @JoinColumn(name="conference_id")
    @ManyToOne(fetch = FetchType.EAGER)
    @OnDelete(action = OnDeleteAction.CASCADE)
    private Conference conference;

    //...
}

@Entity
public class Conference {

    @Id
    @GenericGenerator(name = "UseExistingIdOtherwiseGenerateUsingIdentity", strategy = "xyz")
    @GeneratedValue(generator = "UseExistingIdOtherwiseGenerateUsingIdentity")
    @JsonSerialize(using = ToStringSerializer.class)
    private Long id;

    private String creatorIdentifier;

    private String conferenceName;

    private String conferenceYear;
}

@Entity
public class SubmissionAuthorRecord {

    @Id
    @GenericGenerator(name = "UseExistingIdOtherwiseGenerateUsingIdentity", strategy = "xyz")
    @GeneratedValue(generator = "UseExistingIdOtherwiseGenerateUsingIdentity")
    @JsonSerialize(using = ToStringSerializer.class)
    @Column(name = "s_author_id")
    private Long id;

    private String dataSet;

    @Column(name = "s_author_name")
    private String name;
}

The submission_author_record_set table looks like the following: