How to prevent accessing sharepoint online through Proxy Network

Hi Experts,

I would like to inquire if there is a way to block access through proxy networks.

Currently, our SharePoint is allowed to access only from the corporate region and block the rest, with access blocked by default through Conditional Access Policy and Network Location settings. However, I have noticed that users outside our corporate region can still access SharePoint by using a proxy of our corporate region, which bypasses the restrictions.

I have not been able to find any options to prevent this. Could someone assist with a solution to address this issue?

Thank you for your help.