I haven't had any issues with support myself however with another vendor I had a problem that support were dragging their feet with.
All I can say is don't sit back and wait, keep contacting support and your Meraki account manager. If you keep doing this your account manager if they want your continued business willl escalate the issue through their channels and when support issues start affecting sales I am sure things will get sorted.
The problem I was having with another vendor resulted in a personal visit from the head of sales for the pacific region and being put in contact with the head product manager for the particular service we were having problems with.
Dont give up, but I also agree you shouldn't be having these problems. I can only assume support is overloaded.
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