Smart phone has the function of number segment screening, which can screen all calls and short messages in the specified number segment. Here, we use a Huawei EMUI9. 1 system mobile phone (the screen methods of other brands are similar, please refer to the following operation methods) to demonstrate the operation process:

First, turn on the phone, find the Dial icon and click Open.

2. After entering the dialing interface, click "Three Points"-"Harassment Interception" in the upper right corner.

Third, click "Interception Rules" in the lower right corner of the harassment interception interface.

Fourth, find the Blacklist option and click Open.

5. Click "+"at the bottom of the interface, and then click "First Number Matching" in the pop-up options.

6. After starting the initial number matching, enter the number segment to be blocked, and click OK (if you want to block all Hong Kong calls, just enter the area code "00852"; If you want to block a call in a certain area of Hong Kong, if the other party's call starts with 0085211,please enter 0088.

Seven, as shown in the figure below, after adding the number field at the beginning to match, the number field will be added to the blacklist, and there will be a "*" after it, which means that as long as the number is specified at the beginning, it will be completely blocked.