How to stop automatic payments to Chatr?

i am in India, want to suspend my monthly auto payment.

If you would like to stop the chatr auto-pay preauthorized payment service, you can do so by calling into chatr wireless Customer Care (*611 from your chatr wireless phone - a free call) or by dropping by one of our chatr wireless kiosks all over Canada.

If you were eligible for our chatr auto-pay enrollment bonus credit, the bonus payments will stop upon de-enrollment from chatr auto-pay for any monthly credits remaining.

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How to stop auto payment with Chat-r?