Wireless Backup Time Machine My cloud mirror

Hi, I’ve trying to do time machine backups directly to My Cloud mirror. Even though, I allowed it on my cloud dashboard, when I go to the preferences on time machine backup the cloud mirror doesn’t appear. Am I forgetting something? Can someone help?

Thanks a lot

Double-check your local network settings and map the NAS using AFP.

https://support.wdc.com/knowledgebase/answer.aspx?ID=2686

https://support.wdc.com/knowledgebase/answer.aspx?ID=3561