Sounds like you need to get a call with your SE. Jamf Connects licensing is not complicated, its per device.
You would only need to get a single license to gain access to the product, but you would be violating the EULA to use that single license on multiple devices.
unlike some other comment on here, which is single minded, incorrect, and just garbage....
Jamf does offer an enterprise license as well. while your single license was probably for testing and development, you need one of two licenses. if you're paying individually, you'll need a license for every device. if you have Jamf enterprise, licenses are based on user count as opposed to device/computer account. In the enterprise version, a single license can be used for up to 5 devices.
Make sure you understand your licensing, and the comments here from some people