Thank you so much for your help.
While waiting for your response, I tried something, and it worked. I’d like to share that instead of going with existing products and duplicating them while changing the images for different variants, I attempted creating a new product from scratch, and it worked well. The issue is that this process takes about two hours, as I have to input all the information from scratch, with a significant risk of making errors. Consequently, I would like to go back to the duplication method, even though it’s currently not working.
With this information, do you think you might know where the problem is coming from and how to resolve it? Thanks once again