Hi Krishna,
I’m sorry that you’re running into this error…we are not able to provide technical support here in the Pre-Sales forum, but I will try to point you in the right direction. This article has some steps that you can try, and I would also recommend testing for conflicts with your theme and other plugins to see if you can find anything there.
If you need further assistance with this, I would recommend posting in our community forum, which we review weekly to check for bug reports. Our knowledgebase is a great place to start looking for answers. You can also search our premium forums to see if another user has posted about a similar issue.
If you decide to go ahead with Events Calendar Pro or Event Tickets Plus, you will have access to our premium support forums, where we can provide in-depth support to help you with this further.
Thanks,
Jennifer