(S) Seicento headlining

Hello, I have noticed that the headlining in my Seicento has gathered quite a lot of dust, and I am starting to think that it's mold.

What is the best way to clean it?
Steamer, Water extractor, Autoglym Interior Shampoo?

I've read on multiple websites that steamers and water extractors are a BIG no-no, but I'm asking here just in case someone tried them and can share their experiences. I've already tried using both the Hi-Foam Interior Shampoo (never again, sucks donkey balls) and Interior Shampoo.

Unfortunately, the area where I used Interior Shampoo now sticks out from the entire headlining due to its cleanliness.

I've noticed that the headlining in the Seicento is similar to what I would call a huge cardboard of some sort, if that makes sense. Will it start sagging if soaked?

Thank you,
Moonwilles

'Ammo NYC' on YouTube?

Hey, thanks for the reply.
I've checked this link: https://www.ammonyc.com/detailing/ho...an-headliners/

Is the headlining in the Seicento the same as the car he's working on?

The most effective method seems to be the steam machine.
I've contacted a local upholstery cleaner (I'm getting my seats cleaned using a water extractor), and I was told that a steamer should not be used on headliners, as it's even worse than a water extractor.

I think that whether I like it or not, I'm going to have to stick to Autoglym's Interior Shampoo. It's going to be a pain in the neck, but it seems to have done a good job on the headlining, although not so much on the seats (which is why I'm getting it professionally cleaned).