How to get access to Enterprise Application after assigning user/group?

Hello,

In Azure AD, the Enterprise app "App1" is assigned by "Group1" , however the user of "Group1" are still facing the error as follows when trying to authenticate the App1:

"App1 needs permission to access resources in your organization that only an admin can grant. Please ask an admin to grant permission to this app before you can use it."

Please find the user consent settings is as follows:

Any clue on the error?

Thanks,