@Sisi112 

Hi,
Thank you for the case report. Please ensure the Wi-Fi network that the camera connects to has the internet, disable firewall settings on the router, try to change the router's DNS server to 8.8.8.8/8.8.4.4, and then check if the Tapo cam can be controlled remotely.

Please help confirm the following information if the problem remains.
1. Please describe your network diagram, such as the internet--wireless router)))Tapo cam, etc.
What's the model number of your wireless router? Have you configured some settings on the router, such as MAC Filtering, Access Control, Parental Control, etc.? If yes, turn them off for a try.

2. What's the LED status on the TC70?

3. Please ensure your TC70's firmware and the Tapo app are up to date.

4. You can reset and reconfigure the TC70 for a try.

Best Regards