Question

Okay so I’ve been going to the salon and stylist for about a year, I do half black and half silver. However last visit I had after one shampoo my silver hair turned blonde!! I always use color safe or purple shampoo and use cold water. I reached out to my stylist and sent a picture and all the said was she was going to send me home with a free after my next appointment. Which was super frustrating because I’ve been a loyal customer to her. Going every 6 weeks for the last year, it has not been cheap. She should have offered to fix it right away. So I’ve decided I’m going to just try and dye my hair home. Anyway, she uses what she calls a “ten minute color” for the black color and it’s amazing!! It’s stays dark black for several months without fading. Does anyone know what brand it might be?? Thank you in advance!!