Poor Service

I use FNB network on my cell phone, and it is pay as you go. From Monday the 29th I haven't been able to make any calls to Lesotho. Every time when i make a call either a Chinese or Portuguese speaking person answers the phone. And every time i make these calls and these people answer my airtime gets depleted, as these are international calls. i called the device queries department on Wednesday and i was promised that my query will be escalated. On Thursday I got a call and still explained the same issue and the person promised to call me back and until now i haven't received a call. I have been making calls to Lesotho until Monday and now I can't. Can someone please resolve my query. I really don't understand why i should be frustrated by a service that i pay for