Where does google drive setvice account store files?

Question

ASP.NET

Have a nice day, everyone!
We encountered a problem when using a service account when working with Google Drive API v3.
The situation is absurd for me, but I can’t find any information and I don’t understand if I made a mistake.
Service acc. uploads files to the cloud, there are a lot of them and you need to buy a paid place, but here's the problem - all the uploaded files do not belong to the main user under which the service account was created. and who is the administrator of the service acc.
And it would seem - well, okay, because I have full access to the file (I can even delete it), but it takes up disk space on some other one: screen. And buy disk space for a service acc. it is impossible - only for standard it is possible. And it is not even known how much space has been spent, but it is obvious that sooner or later there will be a blockage.
So actually a question - how to overcome it? Where and how should the parameters be set so that the files take up space on the disk of the main user, and not the service account?
Trying to change ownership does not work, error:
Bad Request. User message: "You can't yet change the owner of this item. (We're working on it.)" [400]
Although this method quietly changes the owner of the folder.
An attempt to upload a file, specifying the owner, also does not work - neither the file is loaded, nor there is a response from the API.