Problem: CTCellularPlanStatus.getTokenWithCompletion Returns Nil Token and Nil Error When Multiple SIM Profiles Are Configured but Only One Subscription Is Active Environment: Device: iPhone 15 Pro iOS: 27.0 Capability: com.apple.developer.upi-device-validation Frameworks: CoreTelephony, MessageUI Reproduced in both production app and standalone Objective-C sample app Issue: After successful UPI verification SMS submission, setUPIVerificationCodeSendCompletion returns YES, but CTCellularPlanStatus.getTokenWithCompletion returns: Token = nil Error = nil Code: [messageController setUPIVerificationCodeSendCompletion:^(BOOL result) { if (result) { [CTCellularPlanStatus getTokenWithCompletion:^(NSString *token, NSError *error) { NSLog(@"Token = %@", token); NSLog(@"Error = %@", error); }]; } }]; Observed Behavior: The behavior appears to depend on the SIM profile configuration: Scenario 1 Device has only a single SIM profile configured: Physical SIM only, or eSIM only Result: Token is returned successfully. Scenario 2 Device has both Physical SIM and eSIM profiles configured and both are active. Result: Token is returned successfully. Scenario 3 The device is configured with both a Physical SIM profile and an eSIM profile; however, only one subscription is active: Physical SIM active, eSIM disabled, or eSIM active while the Physical SIM is removed or unavailable (displayed as "No SIM" in Settings) Observed Result: Token = nil Error = nil Summary of Observed Behavior Token retrieval succeeds in the following configurations: Device provisioned with a single SIM profile (Physical SIM only or eSIM only). Device provisioned with both Physical SIM and eSIM profiles, with both subscriptions active. Token retrieval consistently fails in the following configuration: Device provisioned with both Physical SIM and eSIM profiles, but only one subscription is active. This behavior appears reproducible and suggests a potential issue related to subscriber resolution when a dual-SIM device contains multiple SIM profiles but only a single active subscription. The API does not provide an error indicating why token generation or retrieval failed.