Lost iris+ during auto flight

I just lost my Iris+ while flying it on a mission. I have put it on about 5 auto missions now and this is the first time the drone has disappeared from me. I checked the APMplanner for last coordinates and it gave me the coordinates, but it keeps changing. Any advice for how I can deal with this?

Note: I have the iris+ programmed to RTL when battery goes below 10.5V. Remote was Beeping as it normally does when you lose the signal. It also showed me that it had reached 10.4V for a minute, but then the remote changed back to say 10.5V.