Amplify CLI hangs for hours when creating API models

Question

I have a test Android app using Amplify Auth. Everything works as expected.

I then tried updating the Auth category to add user pool groups and an admin queries API. When running push, the build hangs at "Creating API models..." So I closed Android Studio and tried again, with the same result.

I then removed Auth (and user pool groups, the lambda function and API) and added Auth again (amplify add auth).

Here are the options I selected for the API:

Do you want to add User Pool Groups? Yes
? Provide a name for your user pool group: admin
? Do you want to add another User Pool Group Yes
? Provide a name for your user pool group: users
? Do you want to add another User Pool Group No
√ Sort the user pool groups in order of preference · admin, users
Do you want to add an admin queries API? Yes
? Do you want to restrict access to the admin queries API to a specific Group Yes
? Select the group to restrict access with: admin

When running push, it again hangs at:

Creating API models...
/ Updating resources in the cloud. This may take a few minutes...

After more than 2 hours I closed Android Studio.

Appreciate any help in solving this problem. Thanks.