Seems to have become a common problem, but my Ewelink devices have gone after moving my hub. Same network, LAN enabled, cameras won’t get picked up now either. Even tried a factory reset and that’s made no difference. Only had this a few days and I’m pulling my hair out 
Only thing left to try, is reformatting the SD card 
Edit: No improvement with reformatting card. Replaced it with a 256gb Sandisk Extreme, formatted no problem and seems to work fine. Still no Ewelink devices