Csv file not registering all calls from cdr

Hi people, recently i have been presenting troubles when i download the csv file with all the log files from CDR, the real issue is that when i open the csv file on excel, this one its not showing me all the calls from cdr there are missing logs from calls that i can see on CDR, but not in the csv file on excel and i already changed the cdr_csv.php file for one of another server with the same version of free pbx, in this case the 7.2 version , thinking may be it was a toruble with this file , tried again but it is not working, still missing logs , what could i do ?