Do you have a Samsung Android? Just in case you do, you will also need to enable the "connect to nearby device" in settings (at or near the bottom). My Samsung Android will not function for Follow Me unless I have it enabled along with the GPS function. Hope this helps!
The number of satellites displayed on the screen are the ones that the aircraft sees. Follow Me mode requires your phone/tablet to be able to receive satellites in order to tell the aircraft where you are, and this is what the message on the screen is saying, that the phone/tablet is not receiving the GPS signals well enough to do the job.
Personally, I find a phone too small to see properly, particularly in bright conditions. You might think about getting an iPad Mini, from the Mini 2 upwards, with cellular capability. The Apple iPad products seem to be the most reliable for use with a Phantom. I have an Air 2, but I did not pay full price for it, I bought one from a pawn shop in excellent condition.
Oh boy, I did not know this. On flight 3 with new P3 Pro I decided to try follow me in my yard. Without warning the aircraft went rogue and drove itself into my house and crashed before I could land or power off..Now both aircraft and controller are inoperative. This is after finding I get image transmission error at any distance or altitude over 110 feet. I am very unhappy and venting. Thanx for listening