plastic surgeon for around $ 750 should do it

wash ur hands with soap a lot n scrub!

A mix of white vinegar WITH freshly squeased lemon juice. You can also rub the lemon (the actual fruit) over the area itself. Use about twice daily… ALWAYS remember to use a moisturiser afterwards to avoid any rashes or blistering, as lemonjuice and vinegar can dry out the skin.

go back to the place and ask if they can take it off for u

Use some alcohol, and rub it off.

1–Moisten the temporary color with baby oil.
2–Wipe the color off the area with rubbing alcohol on a cotton ball.
3–Rinse your skin with warm water
4–Pat dry with a washcloth.
5–Repeat steps 1 through 3 if the tattoo is tenacious.
6–Apply moisturizer if the skin feels slightly dry.
7–Return to your quiet life, knowing that it is a very short walk back
to the wild side.

the henna has stained down into several layers of your skin.
You need to exfoliate the dyed layers of skin to remove the henna.
You can do this by scrubbing, then bleaching if there is still color.
Use a toothpaste for scrubbing , or a bathtub cleanser, then you can use any skin lightener product to finish the process.
good luck.