Dear Ryan,
Thanks for your updates and letting us know the result.
As you have tried all the possible settings in the flow and the issue persists, I'm afraid that the next step may be to collect some network trace when the issue happens and provide it to our related team for further investigation.
Sorry for that we may have limited resources on further checking the issue related logs.
If you aren't the administrator, I suggest you contact the administrator in your school and let him follow the steps in Get support - Microsoft 365 admin | Microsoft Learn to open a support ticket to our related team as soon as possible so that they can check the issue related logs and help you fix the issue at their side directly.
The administrator is always the first person who subscribes the Microsoft 365 business subscription or the IT administrator in your organization.
About admin roles in the Microsoft 365 admin center - Microsoft 365 admin | Microsoft Learn
How do I find my Microsoft 365 admin? - Microsoft Support
To simplify the process, I'd like to summarize the issue as follows.
Issue Symptom:
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When running a flow triggered by when a new item is created in a SharePoint Online list, the "BadGateway", "Request to Graph API has timed out." and "Too many requests to Graph API. Please try again later." error messages will pop up and some submitted instances will always fail in the third step "Add a row to a table".
Issue Environment:
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Power Automate
Can be Reproduced?
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No, we can't re produce the issue in our environment after creating a flow with the same configuration.
Ways have been tried:
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- Confirm that the flow hasn't been beyond the limits.
- Set the concurrency in Concurrency Control.
- Set the custom retry policy.
Next Step:
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Collect the network trace when the instance fails and open a support ticket to our related team for further investigation.
Thanks for your understanding and hope that the issue can be soon resolved by our related team!
Sincerely
Cliff | Microsoft Community Moderator