@Dasy2k1 

Hello Daisy,

Thank you for the screenshot.  Try to sign out of the Kasa App and sign back in.  You will need you phone to be connected to the home wifi in order to add a device, so make sure you are connected.  Then after that you should be able to add the devices once more. 

@Bre I'm having this issue and it's really aggravating me. I can only add these things on one phone and I've gotten a new phone and it will not let me add my devices to them. I've removed the devices from the old phone which claims out resets the devices, yet it won't let me add them to the new phone on the app. But I can add them to the old phone app. This is ridiculous. I'm about to demand a refund and go with another company altogether. The fact that this hasn't been replied to work an answer yet is appalling. It's quite simple. It finds the device and goes to add it, then this pops up and basically says nope sorry. Not happening. 

@Bre I went to Setting -> Apps & notifications -> Kasa -> Permissions (allowed all). Restarted phone and tried again. It worked... i had to switch back and forth between being connected via Wifi to my network then the device then back to my network.