Ewelink devices often appear offline

When I link my ewelink account to SmartThings they appear online for a few hours or so then shows offline. And when I re-link my ewelink account the devices again shows online but for a little while. I keep re-linking my ewelink account. Also it never shows up in linked services, it always says no linked accounts. Why is this happening? Is this a regional problem? Why ST so unstable and not like G.home! I really like ST widget. And please add toggle widgets so I don’t have to make two widgets for on and off.
N.B: I don’t have a SmartThings hub