In the Finnish translation of the app, you use the word "lykätä" as translation for "postpone". The correct form is "lykkää".
"Lykkää" is the grammatically correct version of the word "lykätä" when used in a button, as "lykätä" is the nominative form ("to postpone") and "lykkää" is the imperative form ("App, I want you to postpone this.").
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