Please have the serial number and/or Purchase order number and contact support they should be able to help you, in mean while please install 30 trial license to have your network up and running
Resetting a ZD does not reset or remove licenses. Once installed, licenses are permanent. If your licenses are gone then they were never installed. If you have an active support contract you can try contacting support but you’re going to need the sales order number and proof of purchase for the licenses.