If it’s browser cache, you can go into the dev tools and disable all local cache. Browser docs can tell you how to do this.
If it’s the proxy cache, either turn it off or load the site without the proxy, and retest. You will need to consult the documentation for the proxy you’re using for how to do this, and how to fix it. You would be better asking on another stack about your specific proxy software and its configuration.
If it’s the WP cache, then no, WP doesn’t have a page cache. Either disable the plugins providing caching and retest, or consult with their documentation. The solution here will be plugin specific, there is no generic WP solution as there is noo generic WP page caching.
Either start with browser cache and work by peeling away the layers in a process of elimination. Or, by eliminating all of it, and turning it back on 1 layer at a time until the misbehaviour returns. This will give you useful information on how to debug the problem and which layer is problematic.