For some reason my properly licensed Captivate 2017 has started asking for a serial number. When I go to my Adobe.com account and navigate to the downloads and serial numbers page, the downloads show but the serial numbers are missing.
Is it perhaps a subscription license? I will try to find someone from the staff to help you. This is a user forum, and as a user I do not have the power to help you out.
The primary user of the subscription was moved from me (IT support) to our trainer, thus invalidating my use of the license to provide support. After four or five months of both of us having access Adobe shut off my access.
A normal subscription license is exclusively for the Adobe user with the ID linked to the license.