Tuning no space

it says i have no space for tunings
what can i do ? i play on pc

You have to delete some other tunes.

yea i did.

i only have A B C D S1 and S2 one car each class with tuning set up but still no space.

The number of files counts for all cars together.
Perhaps this post in another forum makes it a bit clearer (in German, sorry, but as your screnshot shows the same language, this might not be a hindrance.)
You will need to keep all saved tunings below a certain limit (about 700, I think, but the game does not tell you exactly how much you have downloaded).
Initially I also stored lots of diffent tunes for some cars to compare them (like the Nissan 370 which was the first season challenge car), thus filling up my available slots. Made myself a list of cars to check for “superfluous” tunings and tick these off after clearing them.

That’s why I mostly buy the car again if I want to try another tune, as I reached the tuning file limit several times now, but not the car owner limit (yet).
If I install a tune nowadays, I immediately remove the downloaded file afterwards (the tune stays with the car) and try to keep in mind how much free slots I currently have (about two, I think).