@Axel_D 

Hi, 
Typically, you can follow the instructions below to troubleshoot if your camera keeps going offline.
What should I do if my Tapo smart device keeps losing connection or going offline?
 

For the reported phenomenon, please confirm the following information.
  1. What's the model number of your router? Do you have a stable internet connection when connecting to your router's Wi-Fi?
  2. Please send me (@Solla-topee) the camera's MAC address via a private message.
  3. When the camera has a solid green light but displays offline in your Tapo app, is your phone connected to the same Wi-Fi as the camera? 
  4. Do you have another phone to test if the same phenomenon occurs on it? Please ensure the Tapo app is up to date.
  5. How often does the disconnect phenomenon occur, such as once a day?
  6. When the camera is working, please go to its Device Settings > Device Info page, tap the Wi-Fi icon, and check the RSSI value.

Best Regards