The RE's have had range issues from the start. There's a firmware update on the DJI site. Some people say installing the pagoda antenna helps, others say it doesn't. I getter range with it installed.
Others have done frequency changes in Go4 menus. There are many ideas about the RE range on this forum.
Mine were so bad out of the box I could get clear picture only when going straight up spinning around. At about 300 feet distance, they froze. The updates helped a lot.
I fly in wooded hill country and the weather plays a big part. If it's dry I get a clear view to 1600 feet. I might be able to do better but that's where the property line is and where I turn around.
If it's wet and humid I might make it just past the back yard fence. The RE's are terrible in wet conditions.