PROCEDURE DOESNT WORK

[Serhii Nuzhnyi]

I have such a mysql procedure. It shows no error but do nothing. Cant figure out why.
DROP PROCEDURE IF EXISTS `replbnd`;
delimiter //
CREATE PROCEDURE replbnd()
BEGIN
DECLARE done INT DEFAULT FALSE;
DECLARE done2 INT DEFAULT FALSE;
DECLARE ido INT;
DECLARE brand VARCHAR(255) DEFAULT '';
DECLARE captiono VARCHAR(255) DEFAULT '';
DECLARE brands VARCHAR(955) DEFAULT '';
DECLARE hyphen VARCHAR(1) DEFAULT '-';
DECLARE plus VARCHAR(1) DEFAULT '+';
DECLARE comma VARCHAR(1) DEFAULT ',';
DECLARE space VARCHAR(1) DEFAULT ' ';
DECLARE upperc, camel, element VARCHAR(255);

BLOCK1: BEGIN
DECLARE cur1 CURSOR FOR SELECT caption FROM db.brand_content;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
OPEN cur1;
iterator1: LOOP
FETCH cur1 INTO brand;
IF done THEN
LEAVE iterator1;
END IF;
SET brand = REPLACE(brand, plus, comma);
SET brand = REPLACE(brand, space, comma);
SET brand = REPLACE(brand, hyphen, comma);
SET brand = LCASE(brand);
SET brands = CONCAT(brand, ',', brands);
END LOOP iterator1;
CLOSE cur1;
END BLOCK1;

BLOCK2: BEGIN
DECLARE cur2 CURSOR FOR SELECT id, caption FROM db.catalog_items_content;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done2 = TRUE;
OPEN cur2;
iterator2: LOOP
IF done2 THEN
LEAVE iterator2;
END IF;
FETCH cur2 INTO ido, captiono;

BLOCK3: BEGIN
iterator3 : LOOP
IF LENGTH(TRIM(brands)) = 0 OR brands IS NULL THEN
LEAVE iterator3;
END IF;
SET element = SUBSTRING_INDEX(brands, ',', 1);
SET brands = SUBSTRING(brands, LENGTH(element)+2);
SET captiono = REPLACE(captiono, element, '');
SET camel = CONCAT(UCASE(LEFT(element, 1)), LCASE(SUBSTRING(element, 2)));
SET captiono = REPLACE(captiono, camel, '');
SET upperc = UCASE(element);
SET captiono = REPLACE(captiono, upperc, '');
SET captiono = TRIM(TRAILING space FROM captiono);
SET captiono = TRIM(TRAILING hyphen FROM captiono);
SET captiono = TRIM(TRAILING comma FROM captiono);
SET captiono = TRIM(TRAILING space FROM captiono);
UPDATE db.catalog_items_content SET caption = @captiono WHERE id= @ido;
ITERATE iterator3;
END LOOP iterator3;
END BLOCK3;

END LOOP iterator2;
CLOSE cur2;
END BLOCK2;

END//
CALL replbnd();