Order of my Options in a product keeps reverting back after saving

So I have a product with variants.

One of my Options is ordered [8mm] [10mm] [9.5mm]

I was asked to reorder it in numerical order so it would look like [8mm] [9.5mm] [10mm]

So I did it that way, but when I save the order keeps reverting back to [8mm] [10mm] [9.5mm]

I kept fixing it several times and it keeps reverting it back to

[8mm] [10mm] [9.5mm] no matter what I do.

Does anyone know what is going on?