Poweredge 2600 RAID question

One of the disks in my RAID 5 array went last week. I replaced it with the same model drive (bought refurbed) but the array isn’t rebuilding. Server Administrator is showing the disk as ‘removed’ and doesn’t give me any options. The orange light is blinking on the hard drive (in addition to the server). I did a hot swap and thought the rebuild should happen automatically).