A DevOps engineer is installing a package. The engineer receives the error message
"javax.jcr.nodetype.ConstraintViolationException: OakConstraint0001: /apps/cq/core/content[[nt:folder]]:
No matching definition found for child node with effective type [nt:unstructured]". The installation of the package worked flawlessly on other instances.
What are two possible causes of this issue? (Choose two.)