Dear Alex Behringer,
Greetings! Thank you for posting in Microsoft Community.
Per your description, the issue happens when you try to create a new page on a given site using Power Automate Flow and Microsoft Graph Rest API.
We'd love to help you, considering that we mainly focus on general and build-in queries in SharePoint, we're afraid we may have limited resource for Power Automate flow and Graph Rest API.
At the same time, since we have a dedicated channel Microsoft Power Automate Community, for you to be assisted properly, we sincerely recommend you go to that community and post a new thread. Members and engineers over there are proficient in the knowledge of flow customization queries. They will focus on the specific situation on your side and provide specific suggestions for you.
Meanwhile, for Graph Rest API related queries, please also consider posting a new thread on Microsoft Graph - Microsoft Q&A for more help.
The reason we ask you to post a new thread is n Microsoft Community we have limited resources and very little knowledge about Power Automate and in Microsoft Power Automate Community and Microsoft Graph - Microsoft Q&A, you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction.
Thanks for your understanding and cooperation! We hope you stay safe and healthy always.
Sincerely,
Rhoda | Microsoft Community Moderator