Hello jonnyking,
There currently is no way to combine multiple clips for export. Is your rule configured to trigger when someone or something crosses a boundary or enters/exits a region? If so, these are rules that are triggered instantaneously when the boundary/region is crossed. If a person or object stands on the region/boundary or crosses it multiple times you will receive a clip for each time the boundary or region is crossed. You may find that using inside/outside my region may yield the results you are looking for as it will combine events.
This support article may also be helpful as it has several general tips for those who are seeing too many clips:
https://www.sighthound.com/support/its- ... many-clipsRegards,
-Devin