Any hairdressers can help me please?

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Hi.

I have really blonde hair and my hairdresser uses wella high lift tint in 12.11 with 12% developer. She is going on maternity leave so I got another hairdresser to do my hair. She used to the same colour/measures however my side bits turned pure ash. This happened before at a diff salon despite them using the same product.

when my normal hairdresser puts colour on when it develops it’s seems to go really formy. Also it itches and burns. She swears she doesn’t use bleach on my hair but I don’t understand how I can go to 2 diff places and the sides go pure ash grey?
Can anyone shed any light on what could be happening? My hairdresser has stopped replying now and I just want my hair to be right next time. Thanks
 
I am not a hairdresser.

Sounds like you can use the same product, but the application methods themselves including how long it's been left on would be different with someone else.

My salon has a policy where they say they will fix it for you if you're not happy, but not if you go to another salon. Can you go back to the person instead by text?