On Dashboard, if you want to delete a Freight, you can do as below:

Step 1: Click Rate > Freight > Click the tab of transport that has the freight you want to Delete

Example: I want to delete the first row.

Step 2: Hover your mouse over the Edit button at the last column of freight you want to Delete.

             Then, Click the Delete button.

Step 3: Click the Delete button to confirm the action.

So, you successfully deleted the rate.