Relatively new P3 Pro 4K. Everything seems to function just fine, with one exception. I have an iPad, an iPad Mini and an Android phone. All three have DJI GO app. I can get the P3 Pro to Follow-me on the Android, but on both the iPad devices when I apply, a notice on the upper left of the screen indicate GPS signal too weak. I meet or exceed the altitude required when trying to activate the Follow-me mode. Suggestions?