Symptoms
The account creation API fails to create a cPanel account with a higher "max_email_per_hour" then what is configured in WHM for max emails per hour. However, it is possible to update limits for already existing accounts to a higher max_email_per_hour then what is configured in WHM.
Description
We've opened an internal case for our development team to investigate this further. For reference, the case number is CPANEL-51356. Follow this article to receive an email notification when a solution is published in the product.
Workaround
No workaround is available at this time.