diff --git a/src/controllers/helpers.js b/src/controllers/helpers.js
index 52839728e3..6173402c47 100644
--- a/src/controllers/helpers.js
+++ b/src/controllers/helpers.js
@@ -122,8 +122,7 @@ helpers.notAllowed = async function (req, res, error) {
 
 	if (req.loggedIn || req.uid === -1) {
 		if (res.locals.isAPI) {
-			const cleanedUrl = req.originalUrl.replace(new RegExp(`^${relative_path}`), '');
-			if (cleanedUrl.startsWith('/api/v3')) {
+			if (req.originalUrl.startsWith(`${relative_path}/api/v3`)) {
 				helpers.formatApiResponse(403, res, error);
 			} else {
 				res.status(403).json({