Cannot resolve symbol 'Environment' when importing from com.apple.itunes.storekit.model

Start by reproducing the import failure with the app-store-server-library-java dependency at version 5.1.1 using the pom.xml or build.gradle setup described. Inspect the downloaded JAR entry com/apple/itunes/storekit/model/Environment.class and compare it with the package used by the Java imports; the issue is done when the documented Environment import resolves during a clean Maven or Gradle build.

I'm trying to use the Environment enum from the official app-store-server-library (v5.1.1) in a Java project. However, the IDE reports Cannot resolve symbol 'Environment' no matter which import statement I try:

• import com.apple.itunes.storekit.Environment;
• import com.apple.itunes.storekit.model.Environment;

I have checked the library source JAR and found that inside the model directory, there is an Environment.class file (see attached screenshot). The class seems to exist, but the IDE cannot locate it.

Steps to reproduce:

1. Add dependency to pom.xml (or build.gradle):

   <dependency>
       <groupId>com.apple.itunes.storekit</groupId>
       <artifactId>app-store-server-library</artifactId>
       <version>5.1.1</version>
   </dependency>
   

2. Run mvn clean install (or gradle build).
3. In a Java class, try to import Environment as shown above.
4. Observe compilation error: Cannot resolve symbol 'Environment'.

What I've tried so far:

• Invalidating IDE caches and restarting.
• Deleting .idea and .iml files and re-importing the project.
• Deleting the local Maven repository folder (~/.m2/repository/com/apple/itunes/storekit/app-store-server-library) and re-downloading.
• Checking mvn dependency:tree – no version conflicts.
• Trying both 5.2.0 and 5.1.1 – same issue.
• Manually verifying the JAR with jar tf – the output includes com/apple/itunes/storekit/model/Environment.class.
• Using the fully qualified class name com.apple.itunes.storekit.model.Environment – still unresolved.

Expected behavior:
The class Environment should be resolvable by the IDE and compiler without errors.

Additional notes:

• The library is correctly downloaded to the local repository.
• Other classes from the same package (e.g., ReceiptUtility, SignedDataVerifier) are resolvable without issues.
• My JDK version is 11 (or higher), which meets the library's requirement.

Screenshot attached: Shows the model directory contains Environment.class but the IDE cannot find it.

Thank you for your help.