diff --git a/Rollbar/RollbarDataScrubbingHelper.cs b/Rollbar/RollbarDataScrubbingHelper.cs
index a1882f6..774d4c9 100644
--- a/Rollbar/RollbarDataScrubbingHelper.cs
+++ b/Rollbar/RollbarDataScrubbingHelper.cs
@@ -94,13 +94,17 @@ public virtual ISet<string> GetDefaultFields()
             return new HashSet<string>(
                 new[]
                 {
-                    "Password", 
+                    "Password",
+                    "password",
                     "passwd", 
                     "confirm_password", 
-                    "password_confirmation", 
+                    "password_confirmation",
+                    "AccessToken",
                     "accessToken", 
                     "auth_token", 
-                    "authentication", 
+                    "Authentication",
+                    "authentication",
+                    "Secret",
                     "secret",
                 }
                 );
diff --git a/SdkCommon.csproj b/SdkCommon.csproj
index cba35ac..f03dd78 100644
--- a/SdkCommon.csproj
+++ b/SdkCommon.csproj
@@ -24,12 +24,12 @@
   </ItemGroup>
   
   <PropertyGroup Label="SDK Release Essential Info">
-    <SdkVersion>5.2.0</SdkVersion>            <!-- Required: major.minor.patch -->
+    <SdkVersion>5.2.1</SdkVersion>            <!-- Required: major.minor.patch -->
     <SdkVersionSuffix></SdkVersionSuffix>     <!-- Optional. Examples: alpha, beta, preview, RC etc. -->
     <SdkLtsRelease>false</SdkLtsRelease>      <!-- Optional. Examples: false (default) or true. -->
     <SdkReleaseNotes>                         <!-- Required -->
 
-		feat: resolve #630 - No option to set code_version at the config level in v5 of the SDK
+		fix: resolve #644 - Scrub access token in the message payload
 
 	</SdkReleaseNotes>