To start with, first, ensure that you have a robust internet connection. Now, follow the number of techniques mentioned in this post if you find that
My Yahoo Mail not updating. The issue can arise due to the low Yahoo Mail server. So, visit websites like downdetector.com to check the status of the Yahoo Mail server. Another reason can be the incorrect sync settings are configured. So, ensure that you have correctly configured the sync settings and have turned the sync on. Further, disable the security program on your device and check if the issue is resolved. Moreover, turn off the Windows Defender Security Centre or delete your Yahoo Mail account from the device and add it again.