Cant get the app for ios working

Have some trouble to use the cayenne app for my iphone.
When i use my pc and connect for there it works fine.
But, i cant get it to work from my cayenne app.
if i try to add a item it just say “your device appears to be offline, power up your device and try again”
My device is up and running and i can see my 2 temp.senor live from the webiste from cayenne…
If i pugg out the arduino, esp8266 dev card from my pc and start up the device with battery, then i still see from the website(after it sarts up again)
From my iphone…nothing:(

plz help me.

once you start the app, wait for sometime for the device to be shown as online. once it is highlighted, try adding the sensors.