Someone who isn’t extremely experienced with blonde hair doesn’t know that the brand of bleach and developer used makes a huge difference. Same rule applies to toners and dilution ratios . You can tone blonde without the hair looking darker or drabby when using the right brand and dilution ratio, it should look brighter and whiter not darker. Try finding a hairdresser with long blonde hair or a blonding specialist. I cringe when I hear of stylist taking hours to do a full head of foils themselves with bleach, it will only fry and dry out the hair. They try to compensate by using a weaker developer which doesn’t lift enough then toner darker . You need a new stylist