Disable PIN code on MEDION tablet

Hello everyone, while making a mistake on my Medion Lifetab tablet, I accidentally entered a PIN code that is ruining my access, and now I have to vent about the brand: the integrated user manual is pathetic, except for the 10 pages of safety instructions from Brussels, the brand's online support is, as often, unusable due to mandatory parameters we don't know, and the answers they provide in the FAQs don't work for me. It says that after entering the PIN, you can access the complete lock page where you can disable it by unchecking, but for me, nothing happens; when I entered the PIN, I didn't access anything! Does anyone know the solution please?
thank you in advance for your answers
best regards

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