FreeMarker template error:
The following has evaluated to null or missing:
==> customername  [in template "templates/sso.ftl" at line 6, column 14]

----
Tip: If the failing expression is known to be legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use [#if myOptionalVar??]when-present[#else]when-missing[/#if]. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)!myDefault, (myOptionalVar.foo)??
----

----
FTL stack trace ("~" means nesting-related):
	- Failed at: ${customername?html}  [in template "templates/sso.ftl" at line 6, column 12]
----

Java stack trace (for programmers):
----
freemarker.core.InvalidReferenceException: [... Exception message was already printed; see it above ...]
	at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:131)
	at freemarker.core.EvalUtil.coerceModelToString(EvalUtil.java:355)
	at freemarker.core.Expression.evalAndCoerceToString(Expression.java:82)
	at freemarker.core.BuiltInForString._eval(BuiltInForString.java:26)
	at freemarker.core.Expression.eval(Expression.java:78)
	at freemarker.core.Expression.evalAndCoerceToString(Expression.java:82)
	at freemarker.core.DollarVariable.accept(DollarVariable.java:41)
	at freemarker.core.Environment.visit(Environment.java:324)
	at freemarker.core.MixedContent.accept(MixedContent.java:54)
	at freemarker.core.Environment.visit(Environment.java:324)
	at freemarker.core.Environment.process(Environment.java:302)
	at freemarker.template.Template.process(Template.java:325)
	at org.restlet.ext.freemarker.TemplateRepresentation.write(TemplateRepresentation.java:350)
	at timeedit.web.service.output.TimeEditTemplateRepresentation.write(Unknown Source)
	at org.restlet.engine.application.EncodeRepresentation.write(EncodeRepresentation.java:298)
	at org.restlet.engine.http.HttpServerCall.writeResponseBody(HttpServerCall.java:494)
	at org.restlet.engine.http.HttpServerCall.sendResponse(HttpServerCall.java:431)
	at org.restlet.engine.http.HttpServerConverter.commit(HttpServerConverter.java:416)
	at org.restlet.engine.http.HttpServerHelper.handle(HttpServerHelper.java:150)
	at org.restlet.ext.grizzly.HttpParserFilter.execute(HttpParserFilter.java:81)
	at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:136)
	at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:103)
	at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:89)
	at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:67)
	at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:328)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1095)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:619)
	at java.base/java.lang.Thread.run(Thread.java:1447)