US citizen not living in England received new Fine after previous paid fine refunded.

Next time I will just go 5 under the speed limit at all times. Be back to England soon.

You don't state details of the original offence, but just driving at the limit is fine. Even creeping a couple of mph over the limit is fine.

I went through everyone’s reply and have concluded that there was a step I may have missed

Either a step you missed, the details got mislaid in the post or at receiving end, or perhaps they got confused with your US licence details and deemed you either ineligible for the fine/points (which I thought they could do, just creating a UK ghost record for you), or thought you were having them on. Perhaps did you use a family/friends UK address for yourself, with your US licence details?