The possible cause is that packet loss occurs when the license file is uploaded to the device. As a result, the license file on the device is incomplete. You can run the dir command to check the size of the uploaded file. If the size of the uploaded file is different from that before the upload, re-upload it.
Before re-uploading the license file, run the binary command in the FTP client view to change the file transfer mode to binary mode to improve file transfer stability.