diff --git a/packages/connect-react/src/components/append/AppendAfterErrorScreen.tsx b/packages/connect-react/src/components/append/AppendAfterErrorScreen.tsx
index 8d31d6fe..833c0ef8 100644
--- a/packages/connect-react/src/components/append/AppendAfterErrorScreen.tsx
+++ b/packages/connect-react/src/components/append/AppendAfterErrorScreen.tsx
@@ -63,7 +63,7 @@ const AppendAfterErrorScreen = ({ attestationOptions }: { attestationOptions: st
         void handleErrorSoft(situationCode, true, true, error);
         break;
       case AppendSituationCode.ClientExcludeCredentialsMatch:
-        void handleCredentialExistsError(error);
+        void handleCredentialExistsError(attestationOptions, error);
         break;
       case AppendSituationCode.ExplicitSkipByUser:
         void handleSkip(situationCode, true);
diff --git a/packages/connect-react/src/components/append/AppendInitScreen.tsx b/packages/connect-react/src/components/append/AppendInitScreen.tsx
index e4e03262..c4a8dc66 100644
--- a/packages/connect-react/src/components/append/AppendInitScreen.tsx
+++ b/packages/connect-react/src/components/append/AppendInitScreen.tsx
@@ -244,7 +244,7 @@ const AppendInitScreen = () => {
         setAppendLoading(false);
         break;
       case AppendSituationCode.ClientExcludeCredentialsMatch:
-        void handleCredentialExistsError(error);
+        void handleCredentialExistsError(attestationOptions, error);
         setAppendLoading(false);
         break;
       case AppendSituationCode.DeniedByPartialRollout:
diff --git a/packages/connect-react/src/components/passkeyList/PasskeyListScreen.tsx b/packages/connect-react/src/components/passkeyList/PasskeyListScreen.tsx
index 0a082d63..c0528ae6 100644
--- a/packages/connect-react/src/components/passkeyList/PasskeyListScreen.tsx
+++ b/packages/connect-react/src/components/passkeyList/PasskeyListScreen.tsx
@@ -137,7 +137,11 @@ const PasskeyListScreen = () => {
       }
 
       if (res.val.type === ConnectErrorType.ExcludeCredentialsMatch) {
-        return handleSituation(PasskeyListSituationCode.ClientExcludeCredentialsMatch, res.val);
+        return handleSituation(
+          PasskeyListSituationCode.ClientExcludeCredentialsMatch,
+          res.val,
+          startAppendRes.val.attestationOptions,
+        );
       }
 
       return handleSituation(PasskeyListSituationCode.CboApiNotAvailablePostAuthenticator, res.val);
@@ -171,7 +175,11 @@ const PasskeyListScreen = () => {
     statefulLoader.current.finish();
   };
 
-  const handleSituation = (situationCode: PasskeyListSituationCode, error?: ConnectError) => {
+  const handleSituation = (
+    situationCode: PasskeyListSituationCode,
+    error?: ConnectError,
+    attestationOptions?: string,
+  ) => {
     const messageCode = `situation: ${situationCode}`;
     log.debug(messageCode);
 
@@ -179,7 +187,10 @@ const PasskeyListScreen = () => {
     switch (situationCode) {
       case PasskeyListSituationCode.ClientExcludeCredentialsMatch:
         setAppendLoading(false);
-        void getConnectService().recordEventAppendCredentialExistsError(`${messageCode} ${error?.track()}`);
+        void getConnectService().recordEventAppendCredentialExistsError(
+          attestationOptions ?? '',
+          `${messageCode} ${error?.track()}`,
+        );
         show(<AlreadyExistingModal hide={hide} />);
         break;
       case PasskeyListSituationCode.CboApiPasskeysNotSupportedLight:
diff --git a/packages/connect-react/src/contexts/AppendProcessContext.ts b/packages/connect-react/src/contexts/AppendProcessContext.ts
index 6513b5f3..7335e1ad 100644
--- a/packages/connect-react/src/contexts/AppendProcessContext.ts
+++ b/packages/connect-react/src/contexts/AppendProcessContext.ts
@@ -22,7 +22,7 @@ export interface AppendProcessContextProps {
     error?: ConnectError,
   ) => Promise<void>;
   handleErrorHard: (situation: AppendSituationCode, expected: boolean, error?: ConnectError) => Promise<void>;
-  handleCredentialExistsError: (error?: ConnectError) => Promise<void>;
+  handleCredentialExistsError: (attestationOptions: string, error?: ConnectError) => Promise<void>;
   handleSkip: (situation: AppendSituationCode, explicit?: boolean) => Promise<void>;
   onReadMoreClick: () => Promise<void>;
   flags: Flags | undefined;
diff --git a/packages/connect-react/src/contexts/AppendProcessProvider.tsx b/packages/connect-react/src/contexts/AppendProcessProvider.tsx
index 30cf0d34..e86dcb48 100644
--- a/packages/connect-react/src/contexts/AppendProcessProvider.tsx
+++ b/packages/connect-react/src/contexts/AppendProcessProvider.tsx
@@ -74,10 +74,10 @@ export const AppendProcessProvider: FC<PropsWithChildren<Props>> = ({ children,
   }, [getConnectService, config]);
 
   const handleCredentialExistsError = useCallback(
-    async (error?: ConnectError) => {
+    async (attestationOptions: string, error?: ConnectError) => {
       log.debug('error (credential-exists)');
 
-      await getConnectService().recordEventAppendCredentialExistsError(error?.track() ?? '');
+      await getConnectService().recordEventAppendCredentialExistsError(error?.track() ?? '', attestationOptions);
       void config.onComplete('complete-noop', getConnectService().encodeClientState());
     },
     [getConnectService, config],
diff --git a/packages/web-core/src/services/ConnectService.ts b/packages/web-core/src/services/ConnectService.ts
index 1e9558f4..475369f8 100644
--- a/packages/web-core/src/services/ConnectService.ts
+++ b/packages/web-core/src/services/ConnectService.ts
@@ -644,8 +644,13 @@ export class ConnectService {
     return this.#recordEvent(PasskeyEventType.UserAppendAfterLoginErrorBlacklisted);
   }
 
-  recordEventAppendCredentialExistsError(messageCode: string) {
-    return this.#recordEvent(PasskeyEventType.AppendCredentialExists, messageCode);
+  recordEventAppendCredentialExistsError(messageCode: string, attestationOptions: string) {
+    let challenge;
+    if (attestationOptions) {
+      challenge = WebAuthnService.challengeFromAttestationOptions(attestationOptions);
+    }
+
+    return this.#recordEvent(PasskeyEventType.AppendCredentialExists, messageCode, challenge);
   }
 
   recordEventAppendError() {