"Dost a service" is a phrase that implies helping someone or performing a task or favor for them. The antonyms, or opposite words, for this phrase could include neglect, ignore, harm, hinder, and disservice. Neglect suggests ignoring or failing to attend to someone's needs or requests. Ignoring someone is a deliberate act of avoiding or not paying attention to them. Harming refers to causing harm or damage, either intentionally or unintentionally. Hinder means to obstruct or impede someone's progress or success. Lastly, a disservice is an act that causes harm or disadvantage to someone, often by being unhelpful or doing something wrong.