Thanks everybody for the advices.
The wax thing sound interesting, Illngive it a try maybe before sending, if I find the right product in a DIY shop. Not sure I find the products @Bruce Johnson mentioned because I’m on Italy.
Do all the others, just to be sure, the green Scotchbrite you mentioned is this?
https://amzn.eu/d/bsAMqHw
Yes, try the cleaning and fresh wax first before you mess up the finish. Do they sell Windex in Italy? It's a spray liquid containing some ammonia, made for cleaning windows? You must have something like it in your kitchen cabinet now. It's made for softening and cleaning up dried grease and wax.
The wax I'm referring to used to be called NanoWax a few years ago. By many different brands. Then I guess someone copyrighted the word, or something. Now it's usually called Detailing Wax, or something like that. It's a Carnauba wax, not silicone or ceramic, that's been ground up very fine and is in a liquid in a spray bottle.
Here's the Meguiar's version of "NanoWax":
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