Hi Can anyone please help me.

I  have written a trigger which is working absolutly fine on SANDBOX, but not working on production.

trigger duperror on Sourcing_Tracker__c (before insert) {
    
        
    for(Sourcing_Tracker__c SrcTrc : trigger.new){
    List<Sourcing_Tracker__c> stList=[Select id, CreatedDate, Date_of_Sourcing__c, Date_of_Birth__c, Mobile__c from Sourcing_Tracker__c where Date_of_Birth__c=:SrcTrc.Date_of_Birth__c 
                                          And Mobile__c =:SrcTrc.Mobile__c And Date_of_Sourcing__c= LAST_90_DAYS]; 
      
              
        
        if(stList.size()>0 && SrcTrc.Date_of_Birth__c != Null && SrcTrc.Mobile__c != null){
            system.debug(stList.size());
        SrcTrc.addError('Duplicate Record');
            } 
        }
     }