Where is an invitation code for TestFlight app?

So, where is the invitation code for TestFlight? It all depends on how you were invited to the TestFlight program. Here is a step-by-step guide on how to locate the invitation code:

1. After adding a user for testing, you will receive an email as a user.
2. Open the email on your iOS device and click "Start Testing." This action will direct you to TestFlight to download the app directly.
3. If you open the email on a computer, click "Start Testing." This will lead you to another page with instructions on how to install the app. The invitation code can be found on the last line, typically written in all uppercase letters.
4. Search your email for the TestFlight invitation link. If you are unable to locate the code, check your spam folder as it may have landed there. Otherwise, contact the admin or the person who invited you for the code. They might have a new one available.
5. Sometimes, the invitation code may not work. In such cases, ensure you have accepted all terms and services in the TestFlight app. Navigate to the app, tap it, and accept the terms. If you encounter difficulties accepting the services on the TestFlight mobile app, try opening the TestFlight app via macOS on your desktop. Log in using the same Apple ID, accept all agreements, and attempt to use the TestFlight app from your Mac. Afterward, sign back into the mobile app on your iPhone.

Give these steps a try to locate and use the invitation code successfully.