Items duplication in scenario mode

[nounoursonvii]

Hello everyone ! I was doing the second level of the first scenario of Factorio ("Transport belt madness"). I was about to finish the construction of the belt system but I was missing 2 belts (It's normal). I press the play button to test my system then return to the construction. The whole system is still in place but in my hotbar I have the original number of belts (100 normal and 50 underground) (I attached the image of the situation).

I play on Mac Version (Macbook Air M1), with MacOS Sequoia installed (latest version). I have Space Age installed and the game is up to date. Thank you for your time

[Rseding91]

This is correct. All items are free in this scenario.

[nounoursonvii]

ah okay, thank you very much !