diff --git a/src/activities/Elsa.Activities.Telnyx/Activities/Dial.cs b/src/activities/Elsa.Activities.Telnyx/Activities/Dial.cs
index 08a5d045d..dec870a7d 100644
--- a/src/activities/Elsa.Activities.Telnyx/Activities/Dial.cs
+++ b/src/activities/Elsa.Activities.Telnyx/Activities/Dial.cs
@@ -59,8 +59,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "Enables Answering Machine Detection.",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "disabled", "detect", "detect_beep", "detect_words", "greeting_end" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid })]
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid })]
         public string? AnsweringMachineDetection { get; set; }
 
         [ActivityProperty(
diff --git a/src/activities/Elsa.Activities.Telnyx/Activities/PlayAudio.cs b/src/activities/Elsa.Activities.Telnyx/Activities/PlayAudio.cs
index daf1bc8b8..82cea62c2 100644
--- a/src/activities/Elsa.Activities.Telnyx/Activities/PlayAudio.cs
+++ b/src/activities/Elsa.Activities.Telnyx/Activities/PlayAudio.cs
@@ -76,7 +76,7 @@ namespace Elsa.Activities.Telnyx.Activities
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[]{ "", "self", "opposite", "both" },
             Category = PropertyCategories.Advanced,
-            SupportedSyntaxes = new[] { SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string? TargetLegs { get; set; }
 
diff --git a/src/activities/Elsa.Activities.Telnyx/Activities/SpeakText.cs b/src/activities/Elsa.Activities.Telnyx/Activities/SpeakText.cs
index 9e645cf66..ee0cd84b3 100644
--- a/src/activities/Elsa.Activities.Telnyx/Activities/SpeakText.cs
+++ b/src/activities/Elsa.Activities.Telnyx/Activities/SpeakText.cs
@@ -37,8 +37,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "The language you want spoken.",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "en-US", "en-AU", "nl-NL", "es-ES", "ru-RU" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string Language { get; set; } = default!;
 
@@ -46,8 +45,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "The gender of the voice used to speak back the text.",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "female", "male" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string Voice { get; set; } = default!;
 
@@ -58,8 +56,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "The type of the provided payload. The payload can either be plain text, or Speech Synthesis Markup Language (SSML).",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "", "text", "ssml" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string? PayloadType { get; set; }
 
@@ -68,8 +65,7 @@ namespace Elsa.Activities.Telnyx.Activities
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "", "basic", "premium" },
             Category = PropertyCategories.Advanced,
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string? ServiceLevel { get; set; }
 
diff --git a/src/activities/Elsa.Activities.Telnyx/Activities/StartRecording.cs b/src/activities/Elsa.Activities.Telnyx/Activities/StartRecording.cs
index b5326d303..f4eba772b 100644
--- a/src/activities/Elsa.Activities.Telnyx/Activities/StartRecording.cs
+++ b/src/activities/Elsa.Activities.Telnyx/Activities/StartRecording.cs
@@ -36,8 +36,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "When 'dual', final audio file will be stereo recorded with the first leg on channel A, and the rest on channel B.",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "single", "dual" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string Channels { get; set; } = default!;
 
@@ -45,8 +44,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "The audio file format used when storing the call recording. Can be either 'mp3' or 'wav'.",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "wav", "mp3" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string Format { get; set; } = default!;
 
diff --git a/src/activities/Elsa.Activities.Telnyx/Activities/TransferCall.cs b/src/activities/Elsa.Activities.Telnyx/Activities/TransferCall.cs
index 7a3bcb986..e2848e9f6 100644
--- a/src/activities/Elsa.Activities.Telnyx/Activities/TransferCall.cs
+++ b/src/activities/Elsa.Activities.Telnyx/Activities/TransferCall.cs
@@ -60,8 +60,7 @@ namespace Elsa.Activities.Telnyx.Activities
             Hint = "Enables Answering Machine Detection.",
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "disabled", "detect", "detect_beep", "detect_words", "greeting_end" },
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string? AnsweringMachineDetection { get; set; }
 
@@ -134,8 +133,7 @@ namespace Elsa.Activities.Telnyx.Activities
             UIHint = ActivityPropertyUIHints.Dropdown,
             Options = new[] { "GET", "POST" },
             Category = PropertyCategories.Advanced,
-            DefaultSyntax = SyntaxNames.Json,
-            SupportedSyntaxes = new[] { SyntaxNames.Json, SyntaxNames.JavaScript, SyntaxNames.Liquid }
+            SupportedSyntaxes = new[] { SyntaxNames.Literal, SyntaxNames.JavaScript, SyntaxNames.Liquid }
         )]
         public string? WebhookUrlMethod { get; set; }