Insurance still expensive 25M 3yrs NCB

Just wondering if it’s bad luck or something is wrong.

Licence 3 years old (Manual )

Drive a basic 1.6 diesel civic

3yr NCB

Live in my own flat zone 2 London

Residential parking

6k miles social miles annually

No one else on policy ( can’t add parents )

Insurance for next year renewal quote came to 1.5k

On comparison websites it’s 1.7k

Thought it would be less by now ?