MySQL error in file: /engine/api/api.class.php at line 362

Error Number: 3685

The Error returned was:
Illegal argument to a regular expression.

SQL query:

Select * from dle_post where (category regexp "[[:<:]](209)[[:>:]]") AND approve = 1 AND date < "2024-04-26 16:00:58" AND id != 27544 AND id < 27544 order by id DESC limit 0,20