Windows: run task fails with "Could not find an available drive letter"

My container is configured to mount an FSx volume, which succeeds on first run.

But... each time the task runs and the container exits, it leaves in place the SMB mapping on the EC2 instance:

PS C:\Windows\system32> gdr -PSProvider 'FileSystem'

Name Used (GB) Free (GB) Provider Root CurrentLocation

C 33.87 66.12 FileSystem C:\ Windows\system32 D 0.09 31.91 FileSystem \amznfsxka9h1c5.... E 0.09 31.91 FileSystem \amznfsxka9h1c5.... F 0.09 31.91 FileSystem \amznfsxka9h1c5.... G 0.09 31.91 FileSystem \amznfsxka9h1c5.... H 0.09 31.91 FileSystem \amznfsxka9h1c5.... . . . Z 0.09 31.91 FileSystem \amznfsxka9h1c5....

PS C:\Windows\system32>

Eventually the instance runs out of drive letters, leading to this:

STOPPED (Could not find an available drive letter to mount fsxwindowsfileserver resource on the container instance)

Is there some cleanup I should be doing to ensure the container doesn't leave behind these drive letters?