IF with syntax error

I'm trying to create a simple chat system using database but I want it to automatically automatically truncate when it reaches a rows limit in the database.

The trigger code I made was this:

BEGIN
    SELECT COUNT(*) INTO @a FROM sandbox_webchat;
    IF @a >= 120 THEN
        TRUNCATE sandbox_webchat;
    END IF
END

But he accuses the IF and the END IF as a syntax error, even tested it with the parentheses, but he still accuses the error.

IF (@a >= 120) THEN ... END IF

  

One or more errors have occurred while processing your request:   The following query has failed: "CREATE TRIGGER QuandoAtingirLimite BEFORE INSERT ON sandbox_webchat FOR EACH ROW BEGIN SELECT COUNT (*) INTO @a FROM sandbox_webchat; IF @a> = 120 THEN TRUNCATE sandbox_webchat; END IF END" p>      

MySQL said: # 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 'END' at line 6