php exec function is not working on cpanel

i am using exec php built in function in my project.it is working perfectly on my local but on my cpanel it is not working perfectly. even the code on local and also on cpanel is same but dont know why it is not working.

i know exec function is disabled by default in live server but i have asked to support they are saying that they have enabled exec function but it's not working in my project.

exec code on local:

exec("swetest -edir$sweph -b$utdatenow -ut$utnow -p0123456789DAttt -eswe -house$my_longitude,$my_latitude,$h_sys -flsj -g, -head", $out);

response on local:

194.2488544

also give data in $out in array

exec code on cpanel:

exec("swetest -edir$sweph -b$utdatenow -ut$utnow -p0123456789DAttt -eswe -house$my_longitude,$my_latitude,$h_sys -flsj -g, -head", $out);

response on cpanel:

return empty value.

$out is also empty ...

dont know where the issue coming? cany one one help me to fix this?