Im not sure you would be best off ringing TH but from my past experiance the name does have to be "correct"
Am pretty certain you can change the name on the next stage of court action anyway.. as it asks you to type the name again.. and i am also pretty certain it wont go to court so just do it matt

Ive sent about 8-9 letters over 10 years i have probably proceeded with three with court action all have paid within a day or so once they get the court instructions through the door and adds £65 onto there bill..

.. you would lose £15.00 .. buy hay £25 back is better than nothing.