Warning: Unsupported declare 'strict_types' in D:\xampp\htdocs\masterweb_android_api\vendor\kreait\firebase-tokens\src\JWT\Action\CreateCustomToken.php on line 3

Parse error: syntax error, unexpected ':', expecting ';' or '{' in D:\xampp\htdocs\masterweb_android_api\vendor\kreait\firebase-tokens\src\JWT\Action\CreateCustomToken.php on line 31