In davening we say numerous times ה' הושִׁיעָה. הַמֶּלֶךְ יַעֲנֵנוּ בְיום קָרְאֵנוּ, which translates as "Hashem deliver us, the king will answer us on the day we call".
Why does it say we request from God to answer us on the day we call - aren't we always calling for Hashem to answer us? Why doesn't it say we ask God to answer us while we call him?
Can anyone explain this to me, bring sources or just provide reason.