As he has the 4K model I believe the RTH as a button not the S2 to switch.Hey, Welcome to the forums you may want to go into the dji app setting and make sure that you have return to home selected when it loses connection. also the switch on the top marked as S2, if you flip that a couple of times you will hear a beeping noise and that means its returning home.
Now as for why you had that issues, remember that it uses wifi as a connection and that can be affected by alot of things. it seems you may had some interference. so im not sure someone can tell you that lives in that area.
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