I have table: " daysoff " and table: " rdv "

the rdv table looks like this :

the daysoff table looks like this :

i want to insert values in rdv table, but before inserting any thing i need to check first if " temps_rdv " doesn't exist in the daysoff table

example: I can not add a rdv with temps_rdv = 12-06-2023

I tried a trigger, but it doesn't seem to work

CREATE OR REPLACE TRIGGER TRIGGER1 
BEFORE INSERT ON rdv
FOR EACH ROW
    BEGIN
        IF EXISTS (
            select daysoff.date_off
            From Available daysoff  -- CHANGED THE ALIAS TO A
            where (NEW.temps_rdv = daysoff.date_off)
        ) THEN 
           CALL:='Insert not allowed';

        END IF;
END;