Apple charges imeesage/facetime

After getting an error for activating imessage/facetime, I get charged with international sms. My telecommunication company confirmed that the issue may not be from their side, it is coming from Apple, due to the fact that this issue occures while I tranvelled to the U.S thsn back to Kuwait, where I reside. My telecom conoany is Zain. I need the issue to be fixed so that when I activate them, I wont be charged. My device is an iphone 5 S. Serial Number C7*****5MV IMEI **** my icloud e-mail is **** @icloud.com