Android phones can't always install this software when upgrading, and the reason is that this application has already been installed on the phone, because there is no function on the phone to allow applications from external sources to be installed.

The solution steps are as follows:

1. Take Huawei p20 as an example. First, click the icon to open the "Settings" application on your phone.

2. Then click the Advanced Settings option on this page.

3. Then click the "Security" function option on this page.

4. Then click the switch behind "External Source Application Installation" at the bottom of this page to open, and you can install the application normally.