Why does additional cost interfaced from Projects get Asset Number already in Use error?

Asset creation and initial cost is working fine, but when we try to add new cost to an existing asset, it gives an error that the asset number has already been used.   Does cost addition use a different process to automatically add the new cost to the asset identified in Projects?

Details:

We created asset A1 in Projects, and assigned it to a task.

Asset lines were generated and interfaced to Assets, where the asset was created and the mass addition posted.   Gain/loss, depreciation, etc were run..

So far, so good.

More cost was incurred on asset A1's task in Projects.