Men be noticed to do a lot of research before going to a provider, and make a test for half a month before getting using your host in actual. I have never seen a problem this way, If first 15 days are not good then leave it and see other.
Seems like overselling gone wrong.. If you've paid for 30gb, and are receiving only 5gb, then you should consider moving. What if you had orders to fill? You need to make sure your supplier can actually supply you with what you are purchasing...
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I would try as hard as I can to get your data backed up and everything really needed off of that VS right now, and keep it updated as you do look for an new host, and have it backed up while waiting, as with that, I have never seen that, and I wouldn't be surprised if your VS failed, or was removed, or something else happen.
I would just rather be safe then sorry, and see about getting an refund or at least having them fix it. But for that kind of issue, you shouldn't have to wait no 20+ hours for an reply, and at that at least an reply should come before that.