To be even more specific, using less acronyms..
- Go to your "Communication Service", then Help => Support + Troubleshooting on the left menu.
- Put "Quota Increase" in the tell us about the issue box..
- Which Service => Communication Services -> Next
- Pick your Subscription and Resource for the Communication Service
- One of the following Issues: => Assistance with email Quota Increase => Next
- IMPORTANT PART -- SKIP THE DOCUMENTATION => Need More Help? => Contact Support Tab
- Create a support Request
- 2nd Important part. A lot of the ticket is automatically filled in WRONG. Go to Issue Type, the second input, a change it from "Technical" to "Service and subscription limits (quotas)"
- Quota Type => "Other Requests" => Next
From here you can figure it out.. Fill in the form letter from here and put it in the description: https://learn.microsoft.com/en-us/azure/communication-services/concepts/email/email-quota-increase
Good luck, and hopefully nobody else needs to go through that circular pain. (#6 causes a loop if you follow the MS Docs)