I amworking in the Create a Self-Registration Page section in Trailhead.

I choose a logo, change the registration info to allow external users to self-register.
Then, I assign registering users to profile" Customers and account Customers.

There is an error below "Select which login options to display" (THere is one option displayed
and it is selected) 

I am unable to save my work because of this error.

Has anyone else come up against this issue?

Thanks.