Website isnt opening can anyone help?

[Omnitos]

Since the Increase of bandwidth from 20 gb to 30 gb, website isn't opening and showing this error:
"The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.

Additionally, a 503 Service Temporarily Unavailable error was encountered while trying to use an ErrorDocument to handle the request."

And sometimes it opens but after 5 minutes of wait can anyone help?

 

[cPanelMichael]

Hello,

Your access level shows as "Website Owner". Do you have root access to the server? If not, I recommend contacting your web hosting provider to report the issue. Otherwise if you do have root access, try reviewing /usr/local/apache/logs/error_log to see what's output when you notice that error in your browser.

Thanks!