diff --git a/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/presentation/viewmodel/MainViewModel.kt b/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/presentation/viewmodel/MainViewModel.kt
index 0924ee63..d2838a25 100644
--- a/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/presentation/viewmodel/MainViewModel.kt
+++ b/backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/presentation/viewmodel/MainViewModel.kt
@@ -502,8 +502,25 @@ class MainViewModel @Inject constructor(
                     if (joinResult.sessionStatus == "in_progress") {
                         android.util.Log.d("MainViewModel", "Session already in_progress, triggering keygen immediately")
                         startKeygenAsJoiner()
+                    } else {
+                        // Otherwise, wait for session_started event
+                        // But also poll session status after a delay in case we missed the event
+                        // This handles the race condition where session_started is sent before we're ready
+                        viewModelScope.launch {
+                            delay(2000) // Wait 2 seconds
+                            val joinInfo = pendingJoinKeygenInfo
+                            if (joinInfo != null && joinInfo.sessionId == sessionInfo.sessionId) {
+                                android.util.Log.d("MainViewModel", "Checking session status after delay...")
+                                val statusResult = repository.getSessionStatus(sessionInfo.sessionId)
+                                statusResult.onSuccess { status ->
+                                    if (status.status == "in_progress" && pendingJoinKeygenInfo != null) {
+                                        android.util.Log.d("MainViewModel", "Session is now in_progress (detected via polling), triggering keygen")
+                                        startKeygenAsJoiner()
+                                    }
+                                }
+                            }
+                        }
                     }
-                    // Otherwise, wait for session_started event
                 },
                 onFailure = { e ->
                     android.util.Log.e("MainViewModel", "gRPC join failed", e)