Hello there!
I don’t know how to exactly explain this since I am an UE beginner, but for some reasons when I enable the HeightFog, it conflicts with my RenderTarget’s inventory selection. However, when I turn the heightfog off, it works as normal. Any idea how to get my RT working with the heightfog?
Check the pics ps and let me know 
Bit of a guess here, but have you tried playing with these options in the material?
Hello there! Unfortunately, there isn’t a fog option available since its on UserInterface Material Domain. I tried playing with the options, but it just ended up either not showing up or just a black a figure.
These are the only options I have,
for me i double click on the skysphere blueprint and put it out side of the skysphere facing space not sure if its something you wanna do or not
Well, I am using a light source and Skyatmosphere for the lighting, I don’t have a skysphere…
Render Target Texture Sampler Type should be Linear Colour in Material, but Sampler Type in the texture you showed is Color!, How? is this Texture or Render Target?
I tried with/without Height Fog and Sky Atmoshpere, works well for me, did you changed any options in Fog/SkyAtmoshpere?
I am proud to announce that resetting the height fog options to default indeed fixed my problem, I think it had to do something with the cutoff distance. I thank you all very much for your help <3