FreeSwitch has 20 sample phone number between 1000-1019. It is okay to make a call with these numbers.
I've put 5168880000 number in directory folder. It is okay to call 1000 phone number from 5168880000 phone number. However, calling from 5168880000 to 1000 number has failed. All of variation for 5168880000 directory is same as 1000 number.
I believe that I need to change dialplan config file.. Is there way to make a call for 10 digit number? Thank you.
In the default FreeSWITCH configuration ("vanilla"), dialplan/default.xml contains <extension name="Local_Extension"> which matches 4-digit numbers starting with 10. That's why your 516... numbers do not match.
I would advise to start with the minimal configuration (https://github.com/xlab1/freeswitch_conf_minimal) and build your dialplan as required. The default configuration has too much stuff which needs to be removed.