Hi I am trying to active track my children where the spark will follow them from about 3metres behind them and about 3metres off the ground.  I am finding that the spark tells me that I need to go higher and that the subject needs to be quite a long distance from the spark before it will begin to move. Any suggestions on what I can do.  Thanks so much.

I personally wouldn't active track a person at 3 meters. although I haven't seen any recent posts about drone attacks in active track I feel it's to close to react. I'm not sure if you can change the minimum distance either.

I active tracked myself from fairly close once. As I walked, Phoebe would back way off, then ZOOM up to me then back way off and ZOOM up to me, then back...

I turned off active track and just followed myself manually.

There's a longish video on my youtube channel with Sylvester active tracking me for a long ways, but I had him fairly far off.