Dear James G. Hadley,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
We are sorry to hear that you’re having trouble with setting forms to share outside your organization. I deeply understand the inconvenience this has caused and sincerely apologize for it.
We appreciate your understanding that sometimes the initial response may not resolve the problem immediately. However, we can work together to narrow down and resolve the situation. Unfortunately, your screenshot was not uploaded successfully. Could you please provide the full screenshot as shown below, so that I can offer accurate assistance. 
You can upload the screenshot using this feature:

Additionally, if you prefer assistance via phone call, you will need to create a support ticket with Microsoft Support directly by following the steps provided in this link: Get support - Microsoft 365 admin | Microsoft Learn. Our forum team can only support you via the forum platform.
Once again, I apologize for the inconvenience this has caused. We appreciate your patience and understanding and thank you for your time and cooperation.
Sincerely,
Ralph Chawatama | Microsoft Community Moderator