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Charging customer for a 'yearly subscription', current balance is 1000...
New balance is: 750. Total number of line items is now 1
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Charging customer for a 'monthly subscription', current balance is 686.2...
New balance is: 661.2. Total number of line items is now 3
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Charging customer for a 'one time usage plan with 5000 emails', current balance is 756.2...
New balance is: 606.2. Total number of line items is now 1
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Charging customer for a 'one time usage plan with 100000 emails', current balance is 32.2...
Got error: insufficient funds