David,
ArcGIS Pro and ArcMap share the same Software Authorization Wizard. If you have ArcGIS Pro and ArcMap installed on the same machine, you will notice there's ArcGIS Pro and ArcMap licenses listed when you attempt to deauthorize Single Use licenses. Technically you can use the ArcGIS Administrator from ArcMap or Software Activation Wizard within Pro to authorize/deauthorize Single Use licenses. With that said, ArcMap and ArcGIS Pro have separate set of licenses. In your situation, it sounds like you were attempting to authorize ArcGIS Pro Spatial Analyst extension license using the same authorization number or provisioning file as ArcMap. Go to MyEsri.com > My Organization > Licensing > View Authoriztion to search or verify your authorization number for Spatial Analyst. If you do not have access to these options, you do not have administrative rights to your organization. Have your organization administrator verify it for you.
