diff --git a/src/Akka.Logger.Serilog/SerilogLogMessageFormatter.cs b/src/Akka.Logger.Serilog/SerilogLogMessageFormatter.cs
index d820db3..888023a 100644
--- a/src/Akka.Logger.Serilog/SerilogLogMessageFormatter.cs
+++ b/src/Akka.Logger.Serilog/SerilogLogMessageFormatter.cs
@@ -47,7 +47,8 @@ public string Format(string format, params object[] args)
                 if (propertyToken == null)
                     break;
 
-                properties.Add(propertyToken.PropertyName, new ScalarValue(args[i]));
+                if(!properties.ContainsKey(propertyToken.PropertyName))
+                    properties.Add(propertyToken.PropertyName, new ScalarValue(args[i]));
             }
 
             return template.Render(properties);