Cannot find symbol errors

[hjs2457]

in intellij, Java 8, maven (quickstart), working with a very simple proto 3 file given to me for a project. i followed the instructions and the 2 protobuf jars (protobuf-java:3.19.1 and  protobuf-java-util:3.19.1) are in fact in my "External Libraries". Im getting this error:

Compilation failure

[ERROR] /C:/Users/User/IdeaProjects/CESProject1/src/main/java/org/example/App.java:[14,21] cannot find symbol

[ERROR]   symbol:   class Builder

[ERROR]   location: class com.sampleProject.Product.Proto.ProductProto

I am able to import the Java class ProductProto.java into my App.java which has the main method but when I try to follow along with the instructions in the tutorial page for Writing I get errors when I try to work with Builder.

Please help.

Thank you,

HJS