Hi, I created a Schedulable class to send a CSV file to an email. While I'm testing it I got this error to my e-mail instead of a CSV file. Can anyone help me with this? I'm attaching the code here.

global class ExporterCSV implements System.Schedulable {
    
	global void execute(SchedulableContext sc) {
	List<Contact> conList = [Select id , Lastname, FirstName , CreatedDate , lastModifiedDate from Contact];
	string header = 'Record Id ,Last Name, First Name , Created Date , Modified Date \n';
	string finalstr = header ;
        
	for(Contact a: conList)
	{
   string recordString = a.id + ',' + a.Lastname+',' + a.FirstName + ',' + a.CreatedDate + ',' + a.LastModifiedDate + '\n';
   finalstr = finalstr + recordString;
	}
        
	Messaging.EmailFileAttachment csvAttc = new Messaging.EmailFileAttachment();
	blob csvBlob = Blob.valueOf(finalstr);
	string csvname= 'Contacts.csv';
	csvAttc.setFileName(csvname);
	csvAttc.setBody(csvBlob);
	Messaging.SingleEmailMessage email =new Messaging.SingleEmailMessage();
	String[] toAddresses = new list<string> {'xxxxxxxxxxxxx@gmail.com'};
	String subject = 'Contacts Report CSV';
	email.setSubject(subject);
	email.setToAddresses( toAddresses );
	email.setPlainTextBody('The Contacts report is attached here.');
	email.setFileAttachments(new Messaging.EmailFileAttachment[]{csvAttc});
        
	//Messaging.SendEmailResult [] r = Messaging.sendEmail(new Messaging.SingleEmailMessage[] {email});
	Messaging.sendEmail(new Messaging.SingleEmailMessage[] { email });
	//system.debug(r);
  }
}

Error message I got :

Sandbox
 
Apex script unhandled exception by user/organization: xxxxxxxxxxxxx/yyyyyyyyyyyyyy Source organization: zzzzzzzzzzzzzz (null) Scheduled job 'Email Contact test' threw unhandled exception.
 
caused by: System.LimitException: Apex CPU time limit exceeded
 
Class.ExporterCSV.execute: line 14, column 1