If you are using the pen display in left-hand mode, make sure that you have set up the left-hand mode correctly. Please kindly refer to the following article: Setting Up the Left-hand Mode for Your Huion Tablets
If there is pen offset when your pen display is set as the left-hand mode but you use the pen with your right hand, it is normal.
When you try to check if there is pen offset with your pen display, please make sure that you use left hand to draw if pen display is in left-hand mode. If your pen tip is too far from your mouse cursor, here is the video to fix it: