With soluble inks you generally need to act fast

First, sponge the area around the stain with denatured alcohol. Then apply the alcohol directly on the stain.  Next, place the stain face down on clean white, paper towels. Apply alcohol to the back of the stain. Replace towels frequently. Continue until no further ink is removed. Then rinse thoroughly.

Rub with heavy duty liquid detergent and launder in hottest water safe for fabric, with bleach safe for fabric. Always check for colour-fastness first.

Instead of alcohol, you could use dry cleaning solvent. (Be sure to read and follow the instructions on the product label, these products are toxic) Also, first try a hidden inside seam to be sure any clothing dye won't be affected.

Some inks on white fabric may be removed with a dye stripper. You should be able to find this in areas where package dyes are sold. For stains on coloured fabrics, check for dye stability in a hidden area before using. Also, be aware that these products will affect any colours on the fabric.