This RTMT alert could essentially apply to either your Gateway Route List or a specific Hunt List. Select the alert, and check the detail this should indicate which List was exhausted.
Within either of your route or hunt lists you typically have a list of route-groups or line-groups, and within each of these you have a list of gateway(s) or line-group member(s).
If there are no more available timeslots/channels for listed gateway(s) within the route-group then you receive an alert stating RouteListExhausted. Similarly if you have a line-group where all members are busy for example and the call cannot be routed and you don't have additional line-groups within the hunt-list then same RouteListExhausted message can occur. Hence verify the alert details to establish which.
Regards
Allan.
HTH.
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