I bought several multi-day traffic packages a month. Why do I show that the fixed flow package is successful, but after playing for a while, I am prompted to deduct the fee by SMS?

As you said, if you use Unicom's mobile phone number, this situation can be checked from the following points:

1, the traffic generated before the multi-day traffic package takes effect may be delayed, which means that traffic charges may be generated before ordering the multi-day traffic package;

2. After the multi-day traffic package takes effect, it should be used within the validity period, and then the traffic will be used for normal billing after the expiration;

In your case, I suggest you check the traffic list and traffic usage records through Unicom's online business hall and mobile phone business hall. If you have any questions, you can contact Unicom customer service for help.