These methods or classes that's causing these errors might have either changed or been removed when upgrading Spring Boot.

If you haven't done any of the following, try doing these:

• Remove the import statements where the class/method is failing (e.g. getRuleName(), ResultBuilder). Depending on your IDE, the class name that's not being picked up will be picked up from another path.
• Check your libraries in the pom.xml file and make sure they're compatible for the Spring Boot upgrade. Maybe check if ResultBuilder or RuleManagerDto is coming from a library in your pom.xml. If it has a library, see if upgrading it to a version compatible to Spring Boot 3+ will resolve it.
• I think this was mentioned already, but check if lombok has a compatible version for the Spring Boot upgrade.

Hope this advice helps!

P.S.This is my first StackOverFlow contribution :)