What this mean's?

“Warning: this USB-eLicenser contains a license that enables the usage of VST Transit. Deleting this USB-eLicenser from the account blocks full access to an available VST Transit account.”

I don’t understand this. Please explain me what I must do.

Hi,

When did you get the message?

It seems, you tried to download an USB-eLicenseru from your MySteinberg account and there is a license in this USB-eLicenser. If you delete the USB-eLicenser, you will not be able to use the product anymore.