Iris+ rapidly losing altitude

Please help!
I continue to have problems maintaining altitude while flying the Iris+.
The problem seems to be getting more frequent lately.
I am experiencing this in a variety of flight modes and well as during a mission.
I have tried recalibrating the esc and no improvement.
I have the onboard video and some ground base video as well if needed.
Thanks,
When Iris+ starts to descend I input full throttle and you can see it still landed pretty hard.
[color=#0080FF]https://www.youtube.com/watch?v=fdkqPO6Ykq8[/color]
Flight from ground view
[color=#0080FF]https://www.youtube.com/watch?v=hTQ1ZOLTu10[/color]

Check your log from this flight and see if it went into failsafe from low battery. You can’t really tell much from the video.