You need to add the following dependency to your maven pom.xml:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <version>3.4.5</version>
</dependency>

And also an annotation on the main class @ConfigurationPropertiesScan

@SpringBootApplication
@ConfigurationPropertiesScan
public class DemoApplication {

   public static void main(String[] args) {
      SpringApplication.run(DemoApplication.class, args);
   }

}