Weak signal, poor flight distance

[Gibbana]

I have a Phantom 3 4K, there is no HD symbol on the top right of my flight screen and its not in the settings either??So Im not able to get the Image Transmition Setting screen?? Asking as the drone comes up with weak signal warnings when it's hardly any distance away, i thought I could change channel settings to try and fix the problem? Also the controller doesnt have a USB slot, so im having to use wireless...