I recently changed my wifi password, therefore, all my cameras are not connected anymore to the new network. How can I connect them one by one to the new network/Wifi password I created?

Try this way.There is a reset button hole on the camera. Reset and reinstall the camera.

Can we turn off voice prompt sound ?

Sorry, this is the system setting. If the mobile app does not support changes, there is no way to cancel it.

the camera works and i can see it when i’m home but when i’m at work and i click in the app to see camera it doesnt work. tell me why??

First of all,when installing the camera, choose connect to the router instead of the phone hotspot.On this way, you don't need to find the camera's wifi signal.
For example,you need connect options like this to set.

Hi, One of the bulbs infrared doesn't activate at night, how can I fix that?

Please tell me your order number.I'll check it for you.

Purchased V380Pro lightbulb camera several months ago and have had difficulty setting up.................I finally found instruction manual online, but instructions say to connect camera cord to my phone.......................there is no camera cord....to hold next to WIFI...............as instructions indicate.....................please send email to advise or send cord to BA 3909 Huaco Lane Waco Tx 76710 thank you

You can download the app named "v380pro" in google store.