OpenApi generator maven plugin - field validation (required) ignored - Spring - spring-boot

Question

I use openapi generator maven plugin to generate source code for a spring rest api. Here is the pom:
`<properties>
<maven.compiler.source>17</maven.compiler.source>
<maven.compiler.target>17</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.24</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>2.0.1.Final</version>
</dependency>
<dependency>
<groupId>org.openapitools</groupId>
<artifactId>jackson-databind-nullable</artifactId>
<version>0.2.4</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>3.0.0</version>
</dependency>
<dependency>
<groupId>javax.annotation</groupId>
<artifactId>javax.annotation-api</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.openapitools</groupId>
<artifactId>openapi-generator-maven-plugin</artifactId>
<version>6.2.1</version>
<executions>
<execution>
<goals>
<goal>generate</goal>
</goals>
<configuration>
<inputSpec>${project.basedir}/openapi/openapi.yml</inputSpec>
<output>${project.basedir}/target/generated-sources/swagger</output>
<generatorName>spring</generatorName>
<library>spring-boot</library>
<generateApis>true</generateApis>
<generateModels>true</generateModels>
<modelPackage>...openapi.model</modelPackage>
<apiPackage>...openapi.api</apiPackage>
<supportingFilesToGenerate>ApiUtil.java</supportingFilesToGenerate>
<configOptions>
<delegatePattern>true</delegatePattern>
<useBeanValidation>true</useBeanValidation>
</configOptions>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>`
The code is generated fine, but despite i define a field required in the yml file, it doesnt have any effect - i can send a request with the required field being null and no error thrown. What do i have to do to make the constraints work (others like size limitation arent working either)? I can provide more code, but its simply the generated code with a very simple Delegate implementation.