Trouble with modifying software licenses

We've recently begun to try to do a software inventory and get away from keeping track of licenses by using paper and binders.
As we began to enter what we have on paper into the system so we could scan the computers and compare we quickly realized that we were unable to modify the licenses we'd already entered. Each time we click on "edit license" it shows the screen to enter an entirely new license.

So far the only "fixes" we've been offered is to keep updating to the latest build....which is not changing the functionality.

Is anyone else experiencing this issue or have done their own software inventory and can offer some advice/assistance?