Sequence generator in h2 does not provide unique values

Question

For H2 database in my spring boot api test there is an insertion script that looks something like:

INSERT INTO STORES_TEMPLATE (ID, COUNTRY, TEMPLATE_NAME_1, STORES_1) VALUES(STORES_TEMPLATE_ID_SEQ.NEXTVAL,'country', 'template_name', 'stores');
INSERT INTO STORES_TEMPLATE (ID, COUNTRY, TEMPLATE_NAME_2, STORES_2) VALUES(STORES_TEMPLATE_ID_SEQ.NEXTVAL,'country', 'template_name', 'stores');
INSERT INTO STORES_TEMPLATE (ID, COUNTRY, TEMPLATE_NAME_3, STORES_3) VALUES(STORES_TEMPLATE_ID_SEQ.NEXTVAL,'country', 'template_name', 'stores');

The entity:

@Entity
@Getter
@Setter
@NoArgsConstructor
@Table(name = "STORES_TEMPLATE")
public class StoresTemplate {

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "STORES_TEMPLATE_ID_SEQ")
    @SequenceGenerator(name = "STORES_TEMPLATE_ID_SEQ", sequenceName = "STORES_TEMPLATE_ID_SEQ", allocationSize = 1)
    private Long id;

    @Enumerated(EnumType.STRING)
    private CountryEnum country;

    private String templateName;

    @Lob
    private String stores;

    public void setStores(List<String> stores) {
        this.stores = String.join(",", stores);
    }

    @JsonIgnore
    public List<String> getStoresAsList() {
        return Arrays.stream(stores.split(","))
                .distinct()
                .collect(Collectors.toList());
    }

}

On production oracle database everything works just fine, but on my test environment with h2 database when I try to save new entity the sequence generator gives me ids that are duplicated with the ids of the predefined by the sql migration data. What can I do to fix this issue?

What did the trick was to exclude the insertion script for the tests, but is there another possible solution?