Cannot access my site

Hello....

I'm the admin of http://www.sparkyhub.com/

I don't know what is happening there! From yesterday, i cant access my site from any browsers (only me)

While goes to google chrome:

Oops! Google Chrome could not find http://www.sparkyhub.com

Firefox:

Firefox can't find the server at http://www.sparkyhub.com.

Then I did "Windows troubleshoot on a particular site" and checked my site. It shows an error "DNS Server isn't responding".Please see the screenshot.



When i tried to access my site through mobile (Modem-WiFi) Mobile browser shows "Webpage is not available". So, did "modem" full settings restoration, but no use!

My hosting provider said me that, they flushed the firewall and my IP is not banned there!

But, the ping and traceroute shows an error.Here is the result:

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.
 
C:\Users\AKHIL>Ping sparkyhub.com
Ping request could not find host sparkyhub.com. Please check the name and try ag
ain.
 
C:\Users\AKHIL>Tracert sparkyhub.com
Unable to resolve target system name sparkyhub.com.

I think, an expert can help me..Please help me to resolve my issue.

Note:

OS: Windows 7 Ultimate