No Upfront commitment costs (GRIs, SPs or RIs) can look a bit strange in the "Unblended Cost" cost explorer view when purchased during a month that is still in progress, as AWS attributes the entire cost of the reservation over the month to the day the reservations were purchased.

As the month progresses you will see the cost of those RIs be appropriately "spread out" across the days of usage in the "Amortized Cost" view, ultimately resulting in a lower cost for the month as a whole.