Hi Ken,
Usually depends on the Severity of the issue you have raised, however with Severity 3 you can get a response in less than 8 hours - https://azure.microsoft.com/en-gb/support/plans/response/
It seems the issue might be a complex? Did you received a email confirmation on the incident? If yes there should be a manager contact details, you can approach for escalation and also change the severity of the ticket.
Hope this helps.
JS
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