Game not opening at full screen on all mobile devices

guys i have this problem that took me a long time and I found only one solution for it that requires a manuel build.
but for now i don’t know how to do manuel builds and I want to see if there is any other solutions, this is a screenshot of the problem :

as you can see there is a white area in the bottom of the screen, that problem appears only on mobile devices with 1600px height or higher, and it stills there even after setting the game properties to change the height to fit the screen window size.
pls if any one have a solution help me and thanks.

What is your resolution. Is it set to portrait mode. What is the size of your background image. What is that white thing, is it the color of your background in the scene editor. What is the solution you found that requires a manual build.

so sorry for the late reply Lucky-j I was sick for the few last days, for your questions :
the game resolution is 640 1332 and yes it’s set to portrait mode. the size of the background image is also 640 1332 and as you said that white thing is the color of the background in the scene editor, and about the manuel build solution it’s just a little bit complicated, I did understand it but don’t have enough time to do it for now because I have to learn how manual builds works, and that’s why I’m trying to see if there are any other methods that do not require a manul build… if you want to see how the manual build solution work, you can found it on my old Gdevelop forum topic , just search for :
“Game screen resolution adaptation”
that’s the title of the topic
sorry again for repliying you late my friend