I have successfully download the evaluation license for the Fortigate VM, however I deleted this VM and add a new VM in the EVENG, and this time I failed to download the evaluation license due to the invalid serial number, any solution on this issue.
What do you mean by "downloaded evaluation license" ? Did you get a PDF file with product key to register on the support.fortinet.com, or did you download VM image from the Images download page?
If the 2nd one - you can have only 1 free evaluation license under your FOrtiCloud account, so you would need to delete the VM registered before and removed, and -re-register new VM to this account again.
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