White Microfiber Shirt

My husband has a white microfiber shirt that he loves but it is turning gray and splotchy, particularly on the back. It has some white spots on it from using a bleach pen to remove stains. This just shows how gray the shirt has become. It says not to bleach it but I really want to get it white again! I wonder if our well water could be partly to blame. What should I do?

Miriam from Independence, OR

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