If you change your password in an app account that's connected to Zapier, you must reconnect it. If your app uses:
Basic authentication
You authorized the app by logging in with your username/email and password. You must reconnect the app to Zapier.
OAuth authentication
A dialog box appears from the service asking you to authorize Zapier to access your app account. You may or may not need to reconnect the app to Zapier. Some apps will do it automatically, other do not.
API keys
You entered an API key to connect your account. You do not need to do anything unless you also reset your API key.
Zapier will send you a notification if you must reconnect your app.