I did see that an agent had responded to your voice mail today. Hopefully their response was able to help with your issue!
As for chat, it is dependent on agent availability. If there is more demand than expected at a particular time during the day, then chat will appear as offline. At those times you will need to use another option to reach Box Support.
We'll keep an eye on that availability, though. We want to make sure that the support options we present are effective for our customers.