If more highlights is all you want, then I don't think it would be too much strain to add more highlights, but best ask a professional of course.
Highlights aside, if the base color is too dark for you it depends on:
1) How much lighter do you want to go?
2) How much your hair can handle it
For removal of dark or darker colors, a color remover is generally recommended. (especially for those who have dyed their hair a darker color than their natural hair).
Bleach washes and blue toner shampoo can only do so much.
Beach washes are not very concentrated and like toners (or blue toners to get rid of brassy yellow or orange), are there to just give that extra touch of coolness to neutralize that little bit of yellow or brassiness in the hair.
If you hair can handle it, you may need a color remover + a re-bleach. But of course, the re-bleach would be safer in the 20 volume range. I think a 30 volume is good for yellowish hair or getting roots touched up. 40 volume is way too strong and 10 volume would probably do nothing.
The lower the volume the less damage (theoretically) but the longer it may need time to process on your head. The closer to the scalp, the more warmth, the faster the bleach will process.
Knowing bleach concentrations and timing is everything for processing, as well as understanding the color wheel.
I am not a hairstylist by any means. I just watch a ton of Brand Mondo videos and have learned a lot from him. I used his tutorial to cut my husband's hair during the pandemic and it was great!
If you are comfortable with your current hairstylist, I'd say just go back and explain what you want and, being the person who knows your hair the best, hopefully he or she has the knowledge, understanding, and skill to make things right again. Good luck!