FBM – I don’t seem to be able to create a ‘free shipping’ profile. How do I do this?

The default 3-5 business days at £2.80 is already ticked and I cannot undo it. The other options in the shipping profile list are express delivery and international all with shipping tables already set. I just want to offer free shipping. It’s a second hand book, I typed in the ISBN and found the book but I just cannot find any option to select or create free shipping. I don’t want to get £2.80 shipping credit from Amazon. I have included shipping in the cost. How do I get out of it? I’m om an individual plan if that makes any difference.

Thanks,