I distinctly remember One-Day shipping at 3.99 when I signed up for Prime about 5 years ago, two days ago when I was about to purchase something FREE Two-Day wa

I distinctly remember One-Day shipping at 3.99 when I signed up for Prime about 5 years ago, two days ago when I was about to purchase something FREE Two-Day was available but One-Day sipping was 11.96 on one item and 15.35 on another.