One of the most common reasons why issues like Yahoo not receiving emails occur is because of poor or unstable internet connection. While there could be many other reasons for the occurrence of such issues, you can follow the below-mentioned steps to resolve this problem:

1. Ensure that the device you are using is connected to the internet.
2. Check if the web browser you are using is up-to-date. An outdated web browser can stop you from receiving emails on Yahoo.
3. Check if you have blocked any contacts in your Yahoo Mail account. If yes, unblock them and check if issues like Yahoo Mail not receiving some emails is resolved.
4. Check your Spam folder and see if any email is delivered there.
5. Clear browser cache files and cookies.
6. If you are using the Yahoo Mail app, ensure that you are using the updated version of the app.
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Yahoo mail is not working