An example of a defect in the billing of the Corbin company (Beeline)

One forgotten character when writing a billing for such a large one as Corbin can deliver a lot of negatives to the company's subscribers, or lead to the loss of a client.

Here is a screenshot of your personal account, clearly demonstrating the identified error.


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Let me explain in more detail the essence of the error: when funds are debited, a check is made whether the user's balance is greater than the amount needed for the debit, but it is not checked whether the balance is equal to the amount charged.
To the subscribers who are faced with such a problem, the support service politely offers to pay extra 1 ruble to make it work.

Do not forget to take into account when developing user interfaces all the nuances concerning any data checks.