Ginger roots

[Hooles]

Hello, can everyone help.. I'm a level 6 base with 20% grey with some highlights using 12/1. I do my roots every 4 weeks In between appointments to keep the cost down. I wanted to go lighter on my base/ roots so my hairdresser used 88/0 and 8/38 and it's horrid very brassy and ginger. Can anyone recommend a nice base/root colour that will eliminate any warmth. Many thanks