Hi JDB1
Apologies for the delay in response.
Generally, this can happen if there is not enough stock for the items making up the auto-build item, however, you should still get the window to build or buy those items. Are you getting any error messages while trying to record the invoice? If yes, please attach the screenshot of the error and also check the current quantity on hand for the component items.
I would also recommend clearing the AccountRight cache and then trying to record the invoice again to check if you then get the window for auto-building the items.