Cannot fly multi battery flights

Hi, recently i cannot fly multi battery flights. Every time i load a large flight plan, half way through the first battery it loses signal to the drone and then repicks it up. This then forces the app into thinking that it needs to start the flight, not at the point it finished but at the start of the flight again? It never seems to drop out when flying a flight plan that only needs 1 battery? Any help. This is killing me.

Flying a P4pro obsidian with a Iphone XSmax on ios 12.4.1.

Thanks

I’m not seeing the XS Max on the listed of supported devices, but the X and 11’s are so you would think it should be fine.

Does this happen every time you try multi-battery or just one particular flight plan?

What version of the DroneDeploy app are you running?

Maybe it’s not a matter of lipo battery, it may be a problem with the controller or receiver.