migration issues template error

 <tr class="problemSummary effortTRIVIAL">
        <td>
            <a href="#" class="toggle">FreeMarker template error (DEBUG mode; use RETHROW in production!):
The following has evaluated to null or missing:
==> problemSummary.issueName  [in template "reports/templates/migration-issues.ftl" at line 6, column 42]

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Tip: It's the step after the last dot that caused this error, not those before it.
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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)??
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FTL stack trace ("~" means nesting-related):
	- Failed at: ${problemSummary.issueName?html}  [in template "reports/templates/migration-issues.ftl" in macro "migrationIssuesRenderer" at line 6, column 40]
	- Reached through: @migrationIssuesRenderer problemSummary  [in template "reports/templates/migration-issues.ftl" at line 161, column 37]
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Java stack trace (for programmers):
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freemarker.core.InvalidReferenceException: [... Exception message was already printed; see it above ...]
	at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:131)
	at freemarker.core.EvalUtil.coerceModelToString(EvalUtil.java:355)
	at freemarker.core.Expression.evalAndCoerceToString(Expression.java:82)
	at freemarker.core.BuiltInForString._eval(BuiltInForString.java:26)
	at freemarker.core.Expression.eval(Expression.java:78)
	at freemarker.core.Expression.evalAndCoerceToString(Expression.java:82)
	at freemarker.core.DollarVariable.accept(DollarVariable.java:41)
	at freemarker.core.Environment.visit(Environment.java:324)
	at freemarker.core.MixedContent.accept(MixedContent.java:54)
	at freemarker.core.Environment.visit(Environment.java:324)
	at freemarker.core.Macro$Context.runMacro(Macro.java:184)
	at freemarker.core.Environment.invoke(Environment.java:701)
	at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
	at freemarker.core.Environment.visitByHiddingParent(Environment.java:345)
	at freemarker.core.IteratorBlock$IterationContext.executeNestedBlockInner(IteratorBlock.java:268)
	at freemarker.core.IteratorBlock$IterationContext.executeNestedBlock(IteratorBlock.java:220)
	at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:194)
	at freemarker.core.Environment.visitIteratorBlock(Environment.java:572)
	at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:78)
	at freemarker.core.IteratorBlock.accept(IteratorBlock.java:64)
	at freemarker.core.Environment.visit(Environment.java:324)
	at freemarker.core.MixedContent.accept(MixedContent.java:54)
	at freemarker.core.Environment.visitByHiddingParent(Environment.java:345)
	at freemarker.core.IteratorBlock$IterationContext.executeNestedBlockInner(IteratorBlock.java:240)
	at freemarker.core.IteratorBlock$IterationContext.executeNestedBlock(IteratorBlock.java:220)
	at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:194)
	at freemarker.core.Environment.visitIteratorBlock(Environment.java:572)
	at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:78)
	at freemarker.core.IteratorBlock.accept(IteratorBlock.java:64)
	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.jboss.windup.reporting.freemarker.FreeMarkerIterationOperation.perform(FreeMarkerIterationOperation.java:141)
	at org.jboss.windup.reporting.rules.rendering.RenderReportRuleProvider$FreeMarkerThreadedRenderer$1.call(RenderReportRuleProvider.java:142)
	at org.jboss.windup.reporting.rules.rendering.RenderReportRuleProvider$FreeMarkerThreadedRenderer$1.call(RenderReportRuleProvider.java:125)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)