Complimentary premium plan - Internal server error


I have attempted to create a complimentary premium member for my site. Hoping to use as a test user in the run up to launching my site.

After signing up to the site I logged in to my admin and switched on the “Complimentary premium plan” option.

When I press the save button, it displays an error: Internal server error, cannot edit member. Cannot read property 'id' of undefined

After doing this, I checked my stripe admin portal and the email address used for this test member had been added to the customer list but they did not have a subscription.

Then I added the complimentary subscription to the customer in the stripe admin to see if Ghost would pick up on this.

However, the member details still show: “Member doesn’t have an active Stripe subscription”

I have tried with multiple email addresses to no avail.

I have removed the stripe integration, re-linked it, and tried again. But got the same results.

Wondering if anyone could spot something I am doing wrong or suggest a next step to try?