It may be a setting problem, or it may be that external installation through unofficial channels is prohibited, and it is enough to set it to allow installation. Another possibility is to access the mobile phone housekeeper-rights management-application without authorization, and then select the third-party application to be enabled and turn on-trust this application switch.

Official website, bullfrog assistant-bullfrog assistant is a necessary tool for professional ios mobile terminals, and it is provided to Apple users free of charge: ios mobile terminals use appleid to sign, and there is no need to escape from prison.