Hi All,

I am getting the below exception 

System.StringException: Starting position out of bounds: 11 Class.Test.datecalculation: line 29

Please help me the issue here

public class test {
    
    public static void datecalculation(List<Case> caseList )
    {
        if(caseList.size() >0 )
        {
            List<Case> caseList2  = new List<Case>();
            for(Case c: caseList)
            {
                if(c.Departure_Date_Time__c!=null){
                //Case ca = new Case();
                String firstDate = c.Departure_Date_Time__c;
                String month = firstDate.substring(3,5);
                String day = firstDate.substring(0,2);
                String year = firstDate.substring(6,10);          
                string hour = firstDate.substring(11,13);               
                string minute = firstDate.substring(14,16);               
                string second = firstDate.substring(17,19);
                  
                string stringDate = year + '-' + month + '-' + day + ' ' + hour + ':' 
                    + minute +  ':' + second;
                System.debug('stringDate:'+stringDate);
                
                Date myDate = Date.valueOf(stringDate);
                c.Updated_Departure_Date_Time__c = myDate;
                }
            
            }
        }
        
    }
    
}

ERROR LINE :
                string hour = firstDate.substring(11,13);               

Kindly help me on the same,

Thanks in advance
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