Error Message:

org.apache.sling.api.SlingException: Cannot get DefaultSlingScript: Compilation errors in org/apache/sling/scripting/sightly/apps/wknd/components/content/helloworld/helloworld_html.java: Line 52, column 2348 : com.adobe.aem.guides.wknd.core.models.HelloWorldModel cannot be resolved to a type

Anyone have an idea to solve this error?