diff --git a/src/Core/OAuth2Provider.php b/src/Core/OAuth2Provider.php
index 028b3a7..da19e77 100644
--- a/src/Core/OAuth2Provider.php
+++ b/src/Core/OAuth2Provider.php
@@ -446,7 +446,7 @@ final public function setCodeVerifier(array $params):array{
 	/**
 	 * @implements \chillerlan\OAuth\Core\PKCE::generateVerifier()
 	 * @internal
-	 * @phan-suppress PhanUndeclaredClassMethod
+	 * @phan-suppress PhanUndeclaredClassMethod, PhanUndeclaredMethod
 	 */
 	final public function generateVerifier(int $length):string{