Delimiter error in Stored Procedure

I have this simple code in a procedure:

**DELIMITER // BEGIN

END DELIMITER ;**

And I get this error:

/* SQL Error (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 '// BEGIN

END DELIMITER' at line 11 */

"DELIMITER ..." is a client-only command. The only place in HeidiSQL where you can use that is a query tab. Just remove both of them from the procedure code.