Please come by the Secretary's Office so we can solve your problem [on the spot].
What I want to say instead of the placeholder is that as soon as the person comes to the office (be it today or in a week), we will be able to solve their problem in a short amount of time (as opposed to doing the e-mail dance between the three parties involved and dragging the problem on forever).
Is "on the spot" correct and appropriate for that, or are there better wordings?