Compiler -> Annotation Processors -> Obtain processors from project classpath.

Simply navigate to your .m2 folder -> repository -> projectlombok -> org -> projectlombok -> lombok -> (delete any 'unknown' version if present).

This should automatically set your lombok classpath to the pom.xml version.

Otherwise, you can manually specify the jar from Compiler -> Annotation Processors -> process path.

It should work after that; if not, invalidate the cache and try again once.