Every action triggers new visit


all our tracking is based on identifies users and we also use this information to set the User ID. This usually works find but now I noticed a few instances where every single action a user does generates a new visit: I can see this from the visitor log. Also from there I see that the user ID is the same for all log entries, but the visitor ID changes all the time (and hence generating mutliple entries in the visitor log).

Any ideas what could cause this?

While investigating I also just noticed that for some days the visitor chart shows 0 visits. However when drilling into that day I can see the visitor log containing entries (but every action generating a single click).

Is there any chance that some of the aggregation is in an invalid state? Is it possible to dump all of that and have it regenerated?

Thanks and best regards,