Your Yahoo Mail may not receive the Facebook code for various reasons, and a poor or unstable internet connection is among them. To fix Yahoo Mail not receiving some emails, follow the below steps:
1. First, check your internet connection. If the internet connection is not stable, contact your ISP to resolve the issue.
2. If you don't have issues receiving emails from others and Yahoo not receiving emails from Facebook, look for the missing email in your Yahoo Mail account's Spam, Trash, or Junk folder.
3. Make sure that you have entered your Yahoo Mail address correctly. Re-enter the account address, enter it correctly in the given field and click the Send button.
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