A small narrow yellow/yellow-green leafhopper associated with sedges.  The female has a pointed vertex ('nose') and wider vertex than pronotum.  The males are harder to identify and examination of internal genitalia may be needed to to confirm identification

There are many similar yellow or yellow-green leafhoppers

Good quality photos of a specimen; dissection of male.  You must note host plant/habitat.

wetlands, sedges

Common (ref.: UK Auchenorrhyncha checklist 2021 on British Bugs website)

Rarely recorded; probably overlooked

https://www.britishbugs.org.uk/homoptera/Cicadellidae/Notus_flavipennis.html