Legacy Account
Before the Craft Plugin Store and ExpressionEngine Add-ons Store existed, Solspace managed all purchases and downloads of licenses on its own website. It has been several years since it's been in operation, so chances are, you likely already have your license purchases or moved to the Craft/EE stores. In the event you still need to access old licenses on the Solspace store, you can view them by visiting your Solspace account here:
Solspace Legacy Account