# 16. Call center fee (Hotline number)

When the customer contacts the contact center through the hotline number connected (linked) to the contact center system, the customer will have to bear the fee determined by the network carrier of the hotline number. 

For example: The hotline number is being used to connect to the contact center system of the Mobifone network. Customers' calls will be charged voice fees according to Mobifone network regulations. Hotline numbers of other carriers will apply the same rule. 

In addition, there is a special case of 1900xxxx. If the subscriber runs out of money when calling the contact center, only the first 10 seconds of the call are free.

**Special case number 1800xxxx**

In case the hotline number is 1800xxxx, the contact center will be the one to fully bear the voice fee. Or it can be understood that the customer is free of phone fee when calling into the switchboard system.


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