diff --git a/server/otp.go b/server/otp.go
index 1d51203..d0a5515 100644
--- a/server/otp.go
+++ b/server/otp.go
@@ -77,7 +77,7 @@ func (h *HttpServer) fetchAndValidateOtp(rw http.ResponseWriter, sub uuid.UUID,
 
 func (h *HttpServer) EditOtpPost(rw http.ResponseWriter, req *http.Request, _ httprouter.Params, auth UserAuth) {
 	var digits int
-	switch req.URL.Query().Get("digits") {
+	switch req.FormValue("digits") {
 	case "6":
 		digits = 6
 	case "7":