Mtn
Reports Data available, but not actually available

Hi,
When I dial *141#, it shows that I have 1.15GB of data.
However, after a week of my airtime going down at an extremely fast rate, I realised that my data is not coming off the amount it says is available.
How can MTN report available data if data isn't really available?

Company: Mtn
Country: South Africa
City: Prepaid

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