Did you try changing the wireless channel? How about the signal strengh at the place where the camera pluged? You can have a look at marvr's suggestion to check some settings about your router.

How about the status of system LED? Can you get the wireless connection with a samrt phone where the camera pluged in? It seems the wireless connection disconnected and you need to get it reconnected.

hey, for this issue, it's better to contact support.au@tp-link.com directly. I met this issue before with Archer C5400 V2 and they provide a beta firmware to fix it.

As I know, tplink won't provide API to the third party.

you must have done some troubleshooting with Cassie before. It's better to send email to tplink support for the follow-up.

you may refer to that link on tplink official website. https://www.tp-link.com/en/faq-319.html or you can also add it through utility. https://www.tp-link.com/en/faq-1615.html