Here is the applescript to convert your all phone numbers on contacts that started with “0” to country code. Just replace the “+62” with your country code"
tell application "Contacts"
repeat with aPerson in people
set thePhones to phones of aPerson
if thePhones is not {} then
set errorList to {}
repeat with aPhoneNumber in thePhones
set theNumber to value of aPhoneNumber
if (characters 1 thru 1 of theNumber) as string is "0" then
try
set StringLength to count of characters in theNumber
set newNumber to "+62" & (characters 2 thru StringLength of theNumber)
#display dialog theNumber & " to " & newNumber
set value of aPhoneNumber to newNumber
on error
copy name of aPerson to end of errorList
end try
end if
end repeat
if errorList is not {} then
display dialog "Couldn't change: " & items of errorList
end if
end if
end repeat
save
end tell