It was probably Charles et Charlus, which was a French brand that made gorgeous, high quality bags for a reasonable price. Amazing leather and the prices were only a couple hundred euros.
Unfortunately, they weren't popular enough and they closed last year. You may be able to find them on the secondhand market, especially if you search the French/European sites.
Here's an old post with some pictures of their bags: https://www.parisselectbook.com/en/charles-et-charlus-elegant-bags-that-you-can-personalize/
Thank you so much!! I´ll keep an eye on Evilbay.fr and also on the consignment stores in Brussels. I can´t get that piece out of my head.