Reject a friend request

OpenIMClient.getInstance().friendshipManager.refuseFriendApplication(
    new OnBase<String>() {
        @Override
        public void onSuccess(String data) {
            // Friend request rejected successfully.
        }

        @Override
        public void onError(int code, String error) {
            // Handle the error.
        }
    },
    applicantUserID,
    "Not now"
);