Increasing EBS Volume disk size created a 3rd drive on Windows Disk Management

I have 2 EBS storage volumes attached to a Windows EC2 instance. The volumes were 40gb and 100gb. I increased the 100gb disk to 300 gb, and RDP'ed to the EC2 Windows box ran disk management to allocate the new space to the D drive, but this is what I found instead:

https://pasteboard.co/swhXG4lEqQDA.png

It shows a new drive W that isn't formatted, but has 200gb unallocated to it. Now if I look at the total amount of space available I'd have 40gb (C:/) + 100gb (D:/) + 300gb (W:/)= 440gb!? But in the AWS console I show only 340gb total between 2 EBS volumes. Which brings up the issue that if I format the disk I might be overwriting data because there isn't 440gb allocated. I've tried rebooting the box without success it still shows this extra drive. And I can't find any information about this situation or how to fix it.