A light-roasted coffee may behave differently from a familiar fuller roast. If the cup seems sour, weak or unbalanced, first check the recipe rather than assuming the coffee is defective. The source focuses on water temperature, grind and coffee-to-water balance as connected variables.
Write down the quantities and the brewer used. Change one variable, compare the result and keep the improvement if it is repeatable. A finer grind or a different temperature may be worth testing, but no direction is correct regardless of the equipment and starting recipe.
Taste as the cup cools and consider sweetness, body and finish alongside acidity. Personal preference still matters: learning to brew a lighter coffee does not require enjoying every light roast. A stable baseline makes that judgement more informed than a single hurried attempt.
The conversation
A good question can make a better brew.