get error when i try to consume spec openapi in service project backbase

Question

I'm following A tutorial in backbase academy exactly in chapter "Backbase Backend Essentials Course - Service SDK and Direct Integration Services" and i get error when i try to consume specification from service project , this is the error

exchange-rate-service: Compilation failure: Compilation failure: symbol: method requiredMode() [ERROR] location: @interface Schema

and this is my pom.xml of spec project

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>com.backbase.buildingblocks</groupId>
        <artifactId>backbase-openapi-spec-starter-parent</artifactId>
        <version>11.3.0</version>
    </parent>

    <groupId>com.backbase.training</groupId>
    <artifactId>exchange-rate-specification</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <name>Backbase :: Exchange Rate Specification</name>

    <properties>
        <!-- plugin versions -->
        <boat-maven-plugin.version>0.4.0</boat-maven-plugin.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>com.backbase.oss</groupId>
                <artifactId>boat-maven-plugin</artifactId>
                <version>${boat-maven-plugin.version}</version>
                <executions>
                    <execution>
                        <id>boat-validation</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>validate</goal>
                        </goals>
                        <configuration>
                            <input>${project.basedir}/src/main/resources/openapi.yaml</input>
                            <failOnWarning>true</failOnWarning>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

even with this project i get the same error https://github.com/Backbase/documentation-code-samples/tree/master/service-sdk/11.0.0/create-openapi-spec-project these is the steps that i followed : 1.download project from github 2.run cmd "mvn clean install" on project "messaging-api" until now i get BUILD SUCCESS 3. run cmd "mvn clean install" on project "messaging-service" i get this error

ErrorItem.java:[67,3] error: cannot find symbol symbol: class Schema location: class ErrorItem