diff --git a/Controllers/CookieProxyController.cs b/Controllers/CookieProxyController.cs
index 446f782..3779327 100644
--- a/Controllers/CookieProxyController.cs
+++ b/Controllers/CookieProxyController.cs
@@ -12,7 +12,7 @@ public class CookieProxyController : Controller {
 	[Route("/api/cookieproxy_stage_one")]
 	public IActionResult StageOne([FromQuery] string dstDomain, [FromQuery] string tgt) {
 		// Check if we are on the correct domain
-		if (Request.Host.Host != Vars.AuthProxySubdomain + Vars.UpstreamPrimaryDomain)
+		if (Request.Host.Host != Vars.AuthProxySubdomain + "." + Vars.UpstreamPrimaryDomain)
 			return StatusCode(StatusCodes.Status421MisdirectedRequest);
 		
 		if (!Request.Cookies.ContainsKey("authelia_session")