* I guessed you should be having this issue with only one website. To resolve this, you have to edit the PHP.INI file of the web page.
* If you are using apache server, you can edit it of your own. However, I am not sure how to do this since I have never tried this. I tried so long and couldn't figure out the file from my end. Articles says that it should be configured in the web server.
* If you are using a web server you should be knowing this. In this regard, I would suggest you to refer the below links for assistance:
► Joomla! • View topic - Fatal error: Maximum execution time of 30 seconds exceeded
► How To Find Your PHP.INI
► where do I find the php.ini file? - bluehostforum.com
* If the issue persists, please contact the corresponding website admin, to change the time out settings for you from 30 to some 60 or above !!!
* Keep us posted for further assistance !!!