Stacktrace:
at System.ThrowHelper.ThrowArgumentNullException(ExceptionArgument argument)
at System.Collections.Generic.Dictionary`2.FindValue(TKey key)
at System.Collections.Generic.Dictionary`2.ContainsKey(TKey key)
at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Model.Elements.Worksheets.ConditionalFormattingRuleElementX14.OnAfterRead(IXlsxWorksheetImportContext context) in C:\Work\document-processing\Documents\Spreadsheet\FormatProviders\OpenXml\Xlsx\Model\Elements\Worksheets\ConditionalFormatting\x14\ConditionalFormattingRuleElementX14.cs:line 62