When importing a Nodejs based project through a source control manager integration there are occasionally instances where a package will be suffixed with a version of @unknown. The reference of @unknown means that Snyk is unable to find the versioning information of the package in the provided lock file while the package is required by another package as dependency.
This indicates that the lock file is invalid and the recommendation from the Snyk team is to regenerate the lock file for the project, usually by npm install or yarn. If necessary, the old lock file could be first deleted before the regenerating.