diff --git a/src/ZLogger/LogStates/StringFormatterLogState.cs b/src/ZLogger/LogStates/StringFormatterLogState.cs
index 84cab56..13690d7 100644
--- a/src/ZLogger/LogStates/StringFormatterLogState.cs
+++ b/src/ZLogger/LogStates/StringFormatterLogState.cs
@@ -25,7 +25,7 @@ public StringFormatterLogState(TState originalState, Exception? exception, Func<
 
             if (originalState is IReadOnlyList<KeyValuePair<string, object?>> x)
             {
-                originalStateParameters = x;
+                originalStateParameters = new List<KeyValuePair<string, object>>(x);
                 if (x.Count != 0 && x[^1].Key == "{OriginalFormat}")
                 {
                     ParameterCount = x.Count - 1;