Vodacom
Airtime decreases when phone is not being used

I've been having this problem since I bought the blackberry Z10 phone, my airtime decreases when i dont use my phone. I've spoken to several call agents then they say the problem have been sorted. But when I put on airtime the problem still exists. Is there anyone that can really help.

Company: Vodacom
Country: South Africa
City: Head office

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