Phil Ritchie Welcome to Microsoft Q & A Community Team. I'm sorry to hear that you have not received a response to your quota increase requests. It's possible that the requests were not processed correctly or that there was an issue with the email notifications.
To follow up on your requests, I recommend that you contact Azure support directly. You can open a support ticket from the Azure portal by following these steps:
- Go to the Azure portal and select "Help + support" from the left-hand menu.
- When opening the support request, select Technical as the Issue type.
- Select the subscription of your choice
- Select Machine Learning as the Service.
- Select the resource of your choice
- In the summary, mention "Increase total compute limits"
- Select Compute Cluster as the Problem type and Cluster does not scale up or is stuck in resizing as the Problem subtype.
- On the Additional details tab, provide the subscription ID, region, new limit (between 500 and 2500) and business justification if you would like to increase the total compute limits in this region.
- Finally, select Create to create a support request ticket.
Azure support should be able to investigate the issue and provide you with more information about the status of your requests. For more information, please refer this azure document.