Cannot add a fourth column in a document layout

           javax.servlet.ServletException: javax.servlet.ServletException: org.nuxeo.studio.client.model.StudioException: Failed to build feature with type 'doc' and id 'EndProduct'
	at org.nuxeo.studio.servlet.StudioServlet.service(StudioServlet.java:75)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.webengine.jaxrs.session.SessionCleanupFilter.run(SessionCleanupFilter.java:45)
	at org.nuxeo.ecm.webengine.jaxrs.HttpFilter.doFilter(HttpFilter.java:43)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.webengine.app.WebEngineFilter.doFilter(WebEngineFilter.java:112)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.webengine.jaxrs.context.RequestContextFilter.run(RequestContextFilter.java:42)
	at org.nuxeo.ecm.webengine.jaxrs.HttpFilter.doFilter(HttpFilter.java:43)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.connect.filter.SudoFilter.doFilter(SudoFilter.java:50)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.connect.filter.ConnectUrlFilter.doFilter(ConnectUrlFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.wss.servlet.BaseWSSFilter.doFilter(BaseWSSFilter.java:135)
	at org.nuxeo.wss.servlet.FailSafeWSSFilter.doFilter(FailSafeWSSFilter.java:55)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.platform.ui.web.rest.FancyURLFilter.doFilter(FancyURLFilter.java:131)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.platform.wi.filter.WIRequestFilter.doFilter(WIRequestFilter.java:119)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.platform.web.common.requestcontroller.filter.NuxeoRequestControllerFilter.doFilter(NuxeoRequestControllerFilter.java:142)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.platform.ui.web.auth.NuxeoAuthenticationFilter.doFilterInternal(NuxeoAuthenticationFilter.java:517)
	at org.nuxeo.ecm.platform.ui.web.auth.service.NuxeoAuthFilterChain.doFilter(NuxeoAuthFilterChain.java:35)
	at org.nuxeo.ecm.platform.ui.web.auth.oauth.NuxeoOAuthFilter.doFilter(NuxeoOAuthFilter.java:167)
	at org.nuxeo.ecm.platform.ui.web.auth.service.NuxeoAuthFilterChain.doFilter(NuxeoAuthFilterChain.java:33)
	at org.nuxeo.ecm.platform.ui.web.auth.NuxeoAuthenticationFilter.doFilter(NuxeoAuthenticationFilter.java:339)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.platform.login.web.LoginStackCleaner.doFilter(LoginStackCleaner.java:49)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.platform.web.common.exceptionhandling.NuxeoExceptionFilter.doFilter(NuxeoExceptionFilter.java:79)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.nuxeo.ecm.platform.web.common.encoding.NuxeoEncodingFilter.doFilter(NuxeoEncodingFilter.java:59)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
	at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:190)
	at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:291)
	at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:769)
	at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:698)
	at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:891)
	at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:690)
	at java.lang.Thread.run(Thread.java:662)
Caused by: javax.servlet.ServletException: org.nuxeo.studio.client.model.StudioException: Failed to build feature with type 'doc' and id 'EndProduct'
	at org.nuxeo.studio.servlet.StudioServlet.doBuildProject(StudioServlet.java:155)
	at org.nuxeo.studio.servlet.StudioServlet.doGet(StudioServlet.java:84)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
	at org.nuxeo.studio.servlet.StudioServlet.service(StudioServlet.java:68)
	... 62 more
Caused by: org.nuxeo.studio.client.model.StudioException: Failed to build feature with type 'doc' and id 'EndProduct'
	at org.nuxeo.studio.core.impl.DefaultProject.doBuild(DefaultProject.java:560)
	at org.nuxeo.studio.core.impl.DefaultProject._build(DefaultProject.java:441)
	at org.nuxeo.studio.core.impl.DefaultProject.build(DefaultProject.java:406)
	at org.nuxeo.studio.servlet.StudioServlet.doBuildProject(StudioServlet.java:123)