diff --git a/source/ui/src/main/java/com/clerk/ui/auth/AuthStartViewModel.kt b/source/ui/src/main/java/com/clerk/ui/auth/AuthStartViewModel.kt
index 84a4f1c6b..6f6e914f2 100644
--- a/source/ui/src/main/java/com/clerk/ui/auth/AuthStartViewModel.kt
+++ b/source/ui/src/main/java/com/clerk/ui/auth/AuthStartViewModel.kt
@@ -8,7 +8,6 @@ import com.clerk.api.credentials.shouldFallbackToOAuthFromGoogleOneTap
 import com.clerk.api.credentials.shouldSuppressAutomaticCredentialFlowError
 import com.clerk.api.credentials.shouldSuppressCredentialFlowError
 import com.clerk.api.log.ClerkLog
-import com.clerk.api.network.model.error.ClerkErrorResponse
 import com.clerk.api.network.serialization.ClerkResult
 import com.clerk.api.network.serialization.errorMessage
 import com.clerk.api.network.serialization.onFailure
@@ -180,14 +179,13 @@ internal class AuthStartViewModel(private val ioDispatcher: CoroutineDispatcher
       SignIn.create(SignIn.CreateParams.Strategy.Identifier(identifier = resolvedIdentifier))
         .onSuccess { signIn -> handleSignInSuccess(signIn, transferable) }
         .onFailure {
-          if (withSignUp && it.error is ClerkErrorResponse) {
-            val matchingCodes = listOf(FORM_IDENTIFIER_NOT_FOUND, INVITATION_ACCOUNT_NOT_EXISTS)
-            val hasMatchingError = it.error?.errors?.any { it.code in matchingCodes } ?: false
-            if (hasMatchingError) {
-              signUp(isPhoneNumberFieldActive, identifier, phoneNumber, unsafeMetadata)
-            } else {
-              _state.value = AuthState.Error(it.errorMessage)
-            }
+          val matchingCodes = listOf(FORM_IDENTIFIER_NOT_FOUND, INVITATION_ACCOUNT_NOT_EXISTS)
+          val shouldSignUp =
+            withSignUp && it.error?.errors?.any { error -> error.code in matchingCodes } == true
+          if (shouldSignUp) {
+            signUp(isPhoneNumberFieldActive, identifier, phoneNumber, unsafeMetadata)
+          } else {
+            _state.value = AuthState.Error(it.errorMessage)
           }
         }
     }
diff --git a/source/ui/src/test/java/com/clerk/ui/auth/AuthViewModelTest.kt b/source/ui/src/test/java/com/clerk/ui/auth/AuthViewModelTest.kt
index 8157e9cfa..564af9619 100644
--- a/source/ui/src/test/java/com/clerk/ui/auth/AuthViewModelTest.kt
+++ b/source/ui/src/test/java/com/clerk/ui/auth/AuthViewModelTest.kt
@@ -83,6 +83,53 @@ class AuthViewModelTest {
     }
   }
 
+  @Test
+  fun startAuthWithSignInModeShouldSurfaceApiFailure() = runTest {
+    mockkObject(SignIn.Companion)
+    coEvery { SignIn.create(any<SignIn.CreateParams.Strategy>()) } returns
+      ClerkResult.apiFailure(
+        ClerkErrorResponse(errors = listOf(ClerkError(longMessage = "Couldn't find your account.")))
+      )
+
+    viewModel.state.test {
+      assertEquals(AuthStartViewModel.AuthState.Idle, awaitItem())
+
+      viewModel.startAuth(
+        authMode = AuthMode.SignIn,
+        isPhoneNumberFieldActive = false,
+        phoneNumber = "",
+        identifier = "test@example.com",
+      )
+
+      assertEquals(AuthStartViewModel.AuthState.Loading, awaitItem())
+      assertEquals(AuthStartViewModel.AuthState.Error("Couldn't find your account."), awaitItem())
+    }
+  }
+
+  @Test
+  fun startAuthWithSignInModeShouldSurfaceUnknownFailure() = runTest {
+    mockkObject(SignIn.Companion)
+    coEvery { SignIn.create(any<SignIn.CreateParams.Strategy>()) } returns
+      ClerkResult.unknownFailure(IllegalStateException("Network unavailable"))
+
+    viewModel.state.test {
+      assertEquals(AuthStartViewModel.AuthState.Idle, awaitItem())
+
+      viewModel.startAuth(
+        authMode = AuthMode.SignIn,
+        isPhoneNumberFieldActive = false,
+        phoneNumber = "",
+        identifier = "test@example.com",
+      )
+
+      assertEquals(AuthStartViewModel.AuthState.Loading, awaitItem())
+      assertEquals(
+        AuthStartViewModel.AuthState.Error("Error occurred with unknown message."),
+        awaitItem(),
+      )
+    }
+  }
+
   @Test
   fun automaticPasskeySignInUsesPasskeyStrategy() = runTest {
     val signIn = SignIn(id = "sign_in_123")