diff --git a/app/src/Service/Login.php b/app/src/Service/Login.php
index 1fb1730..3ca0b65 100644
--- a/app/src/Service/Login.php
+++ b/app/src/Service/Login.php
@@ -114,6 +114,10 @@ class Login
             return;
         }
         $cookie = $_COOKIE[$this->cookie_name];
+        if (!str_contains($cookie, $this->cookie_separator)) {
+            $this->removeCookie();
+            return;
+        }
         list($this->selector, $this->token) = explode($this->cookie_separator, $cookie);
     }
     protected function saveCookie(string $selector, string $token, DateTimeInterface $expires): void