Question: I am ready to send my first app to beta testers, so i click on '**Manage Beta**' > '**Manage testers**'

![add a new List with one tester in it](https://i.stack.imgur.com/omaHR.png).

and '**Save**' and '**Resume**'

APK is uploaded > '**Review**'

The review summary says '*This release is ready to be rolled out.*', but the button labled with '**Start to rollout to beta**' is disabled: ![disabled button](https://i.stack.imgur.com/TH9Bd.png).

Answer: 
I had the same problem. In my case I had to agree to "Content guidelines" and "US export laws" listed under "Consent" in "Pricing & distribution" section.
I had same issue. In addition of all this you need to tick **App Content** tab also . Check out the details : [here](https://support.google.com/googleplay/android-developer/answer/9285070?hl=en)