I have a routerboard 411/411R with license level3 RouterOS V3. Today I tried to Netinsall and upgrade it to a newer RouterOS version and a newer key format. Finally I upgraded it to RouterOSv4.1 but as you see in below picture, unfortunately the license key of my routerboard has been gone!! And it could not upgrade the key. It shows Level0

So I'm wondered why it is happened? And what can I do to correct the problem?
Any hint would be very appreciated.