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Hi, I can see here: https://www.conceptstore3d.com/consommables-imprimantes-3d/filaments-pla-spectrum-blanc-175mm-487.html that 250°C is the lowest value of this material temperature range. I would suggest to try at 270°C and 20% fan, this will generally increase mechanical properties of your printed parts by increasing inter-layer adhesion. If you print too hot, the downsides are: i) difficulties to printing overhangs due to micro-retraction of material ; ii) difficulties to remove supports after print.
All the "art" is to find an equilibrium, and a good start is the middle of the manufacturer range, but it is not surprising to me that you get weak inter-layer adhesion with the start value of the range.