If you get"failed to send email" when you set up your Yahoo Email to receive alert.
Please kindly refer to the steps below to fix the issue.
1. Log in your Yahoo email account and go to >Account information like the picture below.
2. Go to >Account security
3. Go to>Generate APP password or Manage APP password.
4. >> Select your APP>> other app>> manually input" Reolink app"
5. Click" Generate" it will generate a password like picture below, please use this new app password as your Yahoo email password to set up your Yahoo email to receive email alert.