Hello! It sounds like you're having trouble receiving the 4-digit code needed to start with the BlockDAG X1 app on your iPhone 8. I’d be happy to help you with that!

Firstly, could you let me know if you registered with your phone number correctly in the app? The 4-digit code is typically sent to the registered phone number you provided during the sign-up process.

Here are a few steps you can try to troubleshoot the issue:

1. Check Your Phone Number: Ensure that the phone number you entered is correct and that it can receive SMS messages.

2. Resend the Code: If possible, look for an option in the app to resend the 4-digit code. Sometimes it may take a moment to arrive.

3. Check Signal & Reception: Make sure your iPhone has a good mobile network signal, as this can affect your ability to receive SMS.

4. Look in Your Message App: Sometimes texts may get filtered into different folders, so please check if the message may have gone to a spam or blocked contacts section.

If you’ve done all of the above and still don’t receive the code, it might be worth checking the user guide for more details, which can be found here.

Let me know how it goes!