A Database Error Occurred

Error Number: 1064

You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '`NULL` AND `rgt` > `IS` `NULL` ORDER BY `lft` ASC LIMIT 1' at line 3

SELECT `id`, `title`, `slug`, `canonical` FROM `products_catalogues` WHERE `lft` < `IS` `NULL` AND `rgt` > `IS` `NULL` ORDER BY `lft` ASC LIMIT 1

Filename: modules/products/models/Frontendproductscatalogues_model.php

Line Number: 123