Error in MySQL stored procedure with variable VARCHAR

The problem is the following: I have an SP in MySQL that receives a variable of type VARCHAR to make a query using the received variable and return a table, the SP worked, all I did was erase the database because I had some problems in some tables, the Fix it in the ER diagram and then export it again using the "Forward Engineer" function, now when I call the SP it does not return anything, but if I call an SP that receives a variable of type INT if it returns data, my question is if I have to change something in the configuration of the database or why do I have this problem now, thanks for the answers

This is the code in question

CREATE PROCEDURE sp_UsuarioListarEstado

(IN _COD VARCHAR(25))

BEGIN
DECLARE EXIT HANDLER FOR SQLEXCEPTION ROLLBACK;

    SELECT ID_USUARIO, USER, NOMBRES, PUESTO, ULTIMO_LOGIN, ESTADO FROM usuario WHERE ESTADO = _COD;

END $$