Last edited by Siva 24 Apr 2020 10:09.
Referring to this error, it is because of mac OS default setting does not allow third party application.
Same thing on iPhone, it does not allow to install applications downloaded outside AppStore, you have to manually 'trust' the Profile.
For your situation,
1.Open System Preferences.
2.Go to the Security & Privacy tab.
3.Click on the lockand enter your password so you can make changes.
4.Change the setting for 'Allow apps downloaded from' to 'App Store and identified developers' from just App Store.
You can refer here for more informations: