"Unable to access service"

I have been calling the Gatehouse, Irvine Central, for almost three weeks. I have called almost everyday, several times throughout the day but cannot get an answer. I understand that due to staffing, prioritizing of services etc, that at some points the phone may not be answered and so would expect to leave a voicemail and someone would return my call. However, when the voicemail clicks on, it tells you to ring back later and not to leave a voicemail as the voicemail is not monitored. I am at a loss as how to access this service. When I first got an appointment several months back, I also had to try ringing everyday for over a week. Surely there must be a better way to access and communicate with this very vital service?