This is hard to diagnose and is not an issue with my app, but here are a few things to try:

  1. If you have changed the wifi password on your router, then you need to re-add the devices using the TP-Link app on iOS or Android.
  2. Your device is having difficulty with a joined 2.4g and 5g wifi:
    • Try separating the bands and connect the device to 2.4g.
    • Create a 2.4g guest wifi network and connect your TP-Link devices to this network.
  3. Try switching the device off at the wall, this can force it to connect and report status to the correct TP-Link regional server.