diff --git a/Export-Excel.ps1 b/Export-Excel.ps1
index 26eb250..4f9a312 100644
--- a/Export-Excel.ps1
+++ b/Export-Excel.ps1
@@ -56,7 +56,7 @@ function Export-Excel {
 
             foreach($format in $ConditionalFormat ) {
                 $target = "Add$($format.Formatter)"
-                $rule = ($ws.ConditionalFormatting).$target($format.Address, $format.IconType)
+                $rule = ($ws.ConditionalFormatting).$target.Invoke($format.Address, $format.IconType)
                 $rule.Reverse = $format.Reverse
             }