Hi, 

I am using omada network using this topology

and i have this problem accessing some website, not all, only few website display this kind of error

but this is only happen when i am using omada network, if i connect the laptop directly to the ISP router, the website can be accessed normally. I even didn't enable any ACL or URL Filtering settings. TP-Link support suggest that i set same DNS settings on Omada Network, this did not solve the problem. since omada didnt have any feature or notification if connection to specific website are blocked or dropped. is there any way to troubleshoot this problem?

Thanks