MySQL foreign key error I need to update rows in a child table,but I am getting following error while I run the code,

Company Table

CREATE TABLE `company` 
(
 `Company_id` int(11) NOT NULL AUTO_INCREMENT,
 `Company_name` varchar(255) DEFAULT NULL,
 `BuildingNameNumber` varchar(255) NOT NULL,
 `Street_name` varchar(255) NOT NULL,
 `Area` varchar(255) NOT NULL,
 `Landmark` varchar(255) NOT NULL,
 `PIN_code` int(6) NOT NULL,
 `PhoneMobile_number` char(15) NOT NULL,
 `Website` varchar(255) NOT NULL,
 `Fax` varchar(255) NOT NULL,
 `Email` varchar(255) NOT NULL,
 `Upload_logo` varchar(255) DEFAULT NULL,
 `tin_number` varchar(50) NOT NULL,
 `CreatedOn` datetime DEFAULT NULL,
 `CreatedBy` varchar(255) DEFAULT NULL,
 `UpdatedOn` datetime DEFAULT NULL,
 `UpdatedBy` varchar(255) DEFAULT NULL,
 `is_active` bit(1) DEFAULT b'0',
 PRIMARY KEY (`Company_id`),
);


Service Table

CREATE TABLE `service` (
`service_id` int(11) NOT NULL AUTO_INCREMENT,
  `company_id` int(11) NOT NULL,
  `serial_number` varchar(256) DEFAULT NULL,
  `service_name` varchar(256) DEFAULT NULL,
  `price` float(10,2) NOT NULL DEFAULT '0.00',
  `tax` float(5,2) NOT NULL DEFAULT '0.00',
  `is_active` bit(1) NOT NULL DEFAULT b'1',
  PRIMARY KEY (`service_id`),
  KEY `company_id` (`company_id`),
  CONSTRAINT `service_ibfk_1` FOREIGN KEY (`company_id`) REFERENCES `company` (`Company_id`) ON DELETE CASCADE ON UPDATE CASCADE
);


When I trying to update the service table I am getting error as 

**Error Code: 1452. Cannot add or update a child row: a foreign key constraint fails (`etailershop`.`service`, CONSTRAINT `service_ibfk_1` FOREIGN KEY (`company_id`) REFERENCES `company` (`Company_id`) ON DELETE CASCADE ON UPDATE CASCADE)  0.031 sec**


I was trying to find the error, I do understand the foreign key constraint but I could not find what is wrong with this, similar structure and constraint tables are working fine.
You're getting this error because you're trying to update a row to service table that does not have a valid value for the company_id field based on the values currently stored in company table.

If you post some more code someone can help you diagnose the specific cause.