I have used the hourglass foundation stick since August. During the previous 2 times I purchased it and completely used it, I had not experienced oxidation at all - the shade match was so perfect and lasted throughout the day.
I recently repurchased it again in the same shade, but the foundation now becomes warm toned and a bit darker throughout the day! I still use the same setting powders as before, so the colour isn’t changing from another product.
What gives? Is there anything I can do to prevent this from happening? Is it a skin issue?