Alarm and Regulations bug

What are you trying to dispatch and what do you have listed in the ARR?

Do you have fire investigator units or fire prevention units?
Also, do you have certain stations set to respond on that ARR?
Last, do you have "exclude from ARR" box checked on any of the units?

Some units, like the Fire Investigator and the Game Warden, function as regular PD units as well. If you don't exclude them from the ARR or make them into their own custom class, this will continue to happen.

Quote from JTMonty

What about when the alarm says “It lacks a certain unit” even when there are plenty of them available?

Yeah, that means that it cant find whatever unit you are trying to dispatch, there could be a couple reasons for this:

1. You only have certain stations set to dispatch through the ARR. For example, if you set stations 1, 2, and 3 to dispatch 1 fire investigator unit but you dont have any at those stations, even if you have one at station 4, it will not dispatch it because its looking for one at 1, 2 and 3.
2. You have "exclude from ARR" checked in the vehicle youre trying to dispatch. Checking this prevents it from dispatching through any ARR, even if you have a custom class set and are trying to dispatch it through a custom class in the ARR.
3. You have "only dispatch this vehicle as its custom class" checked in the vehicle youre trying to dispatch. Checking this prevents it from dispatching as its original class. This means that if you wanted to dispatch a ladder truck but have the class set as something else, it will not dispatch as its original class of platform truck. This is mainly for people who want to dispatch stations instead of number of rigs or are having issues with rigs dispatching through the ARR when they arent supposed to.
4. You have the wrong unit type selected in the ARR. For example, Fire investigators are not fire prevention units but fire investigation units count for both.
5. You dont have enough units to make the ARR work. This would be if you had multiple units dispatched on a single ARR, for example, if you wanted to dispatch 3 engines, 1 ladder, 1 BC, and a fire investigator all from one ARR but you were missing something, you wouldnt be able to dispatch the ARR.