Your answering service is making case selection decisions and nobody trained it
Whoever picks up when the office does not is deciding, in real time, which matters reach a lawyer.
Listen to a week of after hours calls. You will hear callers asked questions your staff would never ask, told things about your practice that are not accurate, and occasionally told you cannot help with something you handle daily.
Give the service a one page brief: the case types you take, the case types you do not, the states you are admitted in, how to describe the consultation, and the exact wording of what happens next. Include the boundary too, since a non lawyer taking messages must not stray into anything resembling advice.
The Illinois question belongs in that brief. Callers from Belleville and Edwardsville will ask whether you can help someone in another state, and the answer, hedged properly, is not obvious to a scheduler reading from a generic script.
Then check monthly. Scripts drift, staff turn over, and the recording is the only place you will see it happen.