I am writing this from the UAE. Last time I put my color clothes together for washing, unfortunately one item got a stain (blue). Can you recommend a remedy?
Not quite sure from your description whether the clothes that were made blue were white or colored. This would make a difference since with white items, I would recommend using a Clorox® Regular-Bleach₂ with CLOROMAX® soak (1/4 cup liquid bleach/gallon of cool water; soak 5–10 minutes then wash in hot water with detergent and liquid bleach), followed by air drying since you may have to repeat the process to get all the color removed.
But if they are colored, it is very difficult (perhaps impossible) to remove the stain without also removing some of the other dye(s). Anything you use in this case should be pretested on a hidden seam (apply, let set for 2–3 minutes, rinse and air dry) to determine how much dye damage is likely to occur and if that is acceptable for you.