Milestones are zero duration tasks that signal the completion of a major event (or start of one).
So, no, you do not allocate resources to milestones – there is no work for any resource to do. If you are trying to say some special meeting (that has some duration on a specific day) is a milestone, that is not a true milestone. What you would do is list the meeting itself as a task with durations, dependencies and resources – then set a milestone (no duration, no resources) as “Customer Meeting Held”, for example.
