After having problems with the previous server, I had to deploy a new server and deploy the application on the new one. On the previous server we never had problems with this part of the application but since we migrated to the new one it has never worked.
OLD SERVER
OS: Linux (3.10.0-1127.18.2.el7.x86_64) 64bit
Java Version: 1.8.0_172 (Oracle Corporation) 64bit
Tomcat Version: Apache Tomcat/8.5.31
Lucee Version: 5.3.6.61
NEW SERVER
OS: Linux (5.15.0-88-generic) 64bit
Java Version: 11.0.20.1 (Eclipse Adoptium) 64bit
Tomcat Version: Apache Tomcat/9.0.80
Lucee Version: 6.0.0.585
“ERROR”,“http-nio-8888-exec-1”,“01/14/2024”,“21:35:37”,“”,"java.lang.NullPointerException;lucee.runtime.exp.NativeException: java.lang.NullPointerException
at org.lucee.extension.pdf.xhtmlrenderer.FSPDFDocument.content(FSPDFDocument.java:127)
at org.lucee.extension.pdf.xhtmlrenderer.FSPDFDocument._render(FSPDFDocument.java:107)
at org.lucee.extension.pdf.PDFDocument.render(PDFDocument.java:359)
at org.lucee.extension.pdf.tag.Document.renderInital(Document.java:849)
at org.lucee.extension.pdf.tag.Document._doAfterBody(Document.java:746)
at org.lucee.extension.pdf.tag.Document.doAfterBody(Document.java:698)
at crearfacturacliente_cfm$cf.call(/crearfacturaCliente.cfm:129)
at lucee.runtime.PageContextImpl._doInclude(PageContextImpl.java:1058)
at lucee.runtime.PageContextImpl._doInclude(PageContextImpl.java:950)
at lucee.runtime.PageContextImpl.doInclude(PageContextImpl.java:931)
at email_es_cfm270$cf.call(/email-es.cfm:14)
at lucee.runtime.PageContextImpl._doInclude(PageContextImpl.java:1058)
at lucee.runtime.PageContextImpl._doInclude(PageContextImpl.java:950)
at lucee.runtime.listener.ClassicAppListener._onRequest(ClassicAppListener.java:65)
at lucee.runtime.listener.MixedAppListener.onRequest(MixedAppListener.java:45)
at lucee.runtime.PageContextImpl.execute(PageContextImpl.java:2494)
at lucee.runtime.PageContextImpl._execute(PageContextImpl.java:2480)
at lucee.runtime.PageContextImpl.executeCFML(PageContextImpl.java:2451)
at lucee.runtime.engine.Request.exe(Request.java:45)
at lucee.runtime.engine.CFMLEngineImpl._service(CFMLEngineImpl.java:1219)
at lucee.runtime.engine.CFMLEngineImpl.serviceCFML(CFMLEngineImpl.java:1165)
at lucee.loader.engine.CFMLEngineWrapper.serviceCFML(CFMLEngineWrapper.java:97)
at lucee.loader.servlet.CFMLServlet.service(CFMLServlet.java:51)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:623)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:209)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:168)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:481)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:130)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:390)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:926)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1790)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.base/java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
… 45 more
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