Hello,
A country code identifies the country to which AP radios belong. Different countries support different AP radio attributes, including the transmit power and supported channels.
It's recommended that you change the value to the code of county where the device located.
Restart the AP after changing the country code.
Please refer to https://support.huawei.com/hedex/hdx.do?docid=EDOC1000055021&id=dc_cfg_wlan_basic_0009&lang=en
I hope this helps.