Google Play Store Internal Test cannot start roll out

Question

I am going to start rolling out the first version of the application to the internal testers.

But the button START ROLLOUT TO INTERNAL TEST is disabled

Answer 1

Seems like filling out all the fields is a requirement per the step 3 of the following page to rollout any release:

https://support.google.com/googleplay/android-developer/answer/7159011?hl=en