I am able to save the trigger but getting the following error while creating / editing the record...

System.NullPointerException: Attempt to de-reference a null object: Trigger.ComplTrigger: line 34, column 1

see my trigger below..

trigger ComplTrigger on Complaint_Inquiries__c (before insert, before update) {

 
   Set<id> AccIds = new Set<id>();
   
    for (Complaint_Inquiries__c c : Trigger.new)
        AccIds.add(c.Account__c);
       
  
    Map<id, Account> AccIDmap = new Map<id, Account>([Select Name, BillingStreet,BillingCity, BillingState, BillingPostalCode from Account Where Id in :AccIds]);     
   
    for (Complaint_Inquiries__c Compl : Trigger.new){
        if(Compl.Copy_From_Account__c == true){
        Compl.Business_Name__c      = AccIDmap.get(Compl.Account__c).Name;
        Compl.Business_Address__c   = AccIDmap.get(Compl.Account__c).BillingStreet;
        Compl.Business_City__c         = AccIDmap.get(Compl.Account__c).BillingCity;
        Compl.Business_State__c       = AccIDmap.get(Compl.Account__c).BillingState;
        Compl.Business_Zip__c           = AccIDmap.get(Compl.Account__c).BillingPostalCode;
        Compl.Copy_From_Account__c = false;
        }
        }
        
        
        Set<id> ContIds = new Set<id>();
   
    for (Complaint_Inquiries__c c : Trigger.new)
        ContIds.add(c.Contact__c);
       
  
    Map<id, Contact> ContIDmap = new Map<id, Contact>([Select FirstName from Contact Where Id in :ContIds]);     
   
    for (Complaint_Inquiries__c Compl : Trigger.new){
        if(Compl.Copy_From_Contact__c == true){
        Compl.Business_Contact_First_Name__c = ContIDmap.get(Compl.Contact__c).FirstName;
        Compl.Copy_From_Contact__c = false;
        }
        }
        
        
        

}

 Please help