Firstly, please check the camera's Focus Mode whether is Automatic Mode, If it is Manual Mode, please change this into Automatic Mode.
Web Adjust method:
Click "Device Control"---->"Video Control" page, Click "A" button to adjust the focus mode into Automatic.
The photo is like the belowing:
RC Adjust Method:
login "Camera control"---->"Adjust Focus", Click "A" button.
Please refer to the belowing photo: