Scripted and Declarative syntaxes are two different approaches to defining your pipeline jobs in Jenkins. When working with the Jenkins Artifactory plugin, be sure to choose either scripted or declarative. In other words, do not use declarative and scripted steps within a single pipeline. This will not work.
More information on the difference between the two can be found in the Jenkins Pipeline Syntax documentation.
Integration Benefits JFrog Artifactory and Jenkins-CI