Error in Power Automate when connecting MS Forms: 'Selected user account does not exist in tenant'

Question

Hello,

I am using MS Forms to collect some responses from people, and I'd like to have the results sent to a specific email address.

I understand that I can use Power Automate to do this (and more), but when I start PA from within Office 365, I select 'Automated Cloud Flow', and then when prompted "When a new response is submitted", and then click 'Create', a prompt is displayed saying "Sign in to create a connection to Microsoft Forms".

When I select my account, and try to log in, the following error message is displayed, and I cannot continue;

"Selected user account does not exist in tenant 'Microsoft Services' and cannot access the application '7ab7862c-4c57-491e-8a45-d52a7e023983' in that tenant. The account needs to be added as an external user in the tenant first. Please use a different account."

Please advise what I need to do to resolve this.

Thanks