2. Click the WLAN column in the Settings list.
3. Then click the exclamation point icon to the right of the currently connected wireless network in the right pane.
4. Then, click the DNS column under wireless network DHCP.
5. Next, please delete the original DNS address, enter a new 8.8.8.8 address, and then click the WLAN button to return.
6. Then please exit the AppStore application from the background and try downloading again. Another situation is that the system version on your current mobile phone is low. Because many softwares will follow Apple's latest system, there are requirements for the version of the system. If you belong to this category, please upgrade your mobile phone system before downloading.