Does the phone even show "obtaining up address" when you click on the Drone's wifi?
What I've noticed on my phone (ZTE Axon 7) is that I will usually have to disable data for the wifi to remain connected. It's usually cause the phone will not stay connected to a wifi network if the network does...
I have this mount installed on mine. This mount places an action cam more forward in order to avoid seeing the landing gear. Give it a look?
Link: Blomiky Camera hold mount for MJX Bugs 3 B3 Drone B3 Camera Frame https://www.amazon.com/dp/B071R81G73/ref=cm_sw_r_cp_apa_a7ZqAb3RDHQRA