I want to be able to execute some code whenever I send a message from my Facebook page to a person. From reading the documentation, I can only find webhooks for inbound messages

Hello, i am facing issue while embaded signup. in embaded signup i am getting the code which is helpful for generate token so it is working but i want the waba and phone number id which i am not able to get i have also setup account_update webhook but still that webhook is not triggering.

"Unexpected null value for wabaID while adding a phone number in WhatsApp API setup."
When attempting to add a phone number in the WhatsApp API setup, an error occurs stating: 'Unexpected null value for wabaID'. This prevents the number from being linked to the WABA.
Expected behavior: The phone number should be added and verified successfully."
Log in to the Meta Developer portal. Navigate to API Setup under WhatsApp. Click on Add Phone Number. Enter a valid phone number. Select a verification method (SMS or call). Click Next. Observe the error.
Thank you, Peter G.

My conversion limit on WhatsApp is not increasing even after I verified my Facebook Business Manager.

I created an app, and follow steps provided. After I click "Add account" in order to get access token, it pop up instagram login window, after login it show "Sorry, something went wrong." as per image attached.
Appreciate if someone can give me advice, thanks.