Hi
Does anyone know if you can get the old and lost dongle deleted, and get a new one? Or should buy a whole new cubase package?
Look at the first two “Requirements” listed in the 2nd link. If OK then proceed as follows.
Purchase a new USE eLicenser dongle here…
https://www.steinberg.net/en/shop/buy_product/sku/502009050.html
Then after you receive it follow the instructions here…
https://helpcenter.steinberg.de/hc/en-us/articles/206532304-Steinberg-Zero-Downtime
Good luck. 
Regards 