groundfeel
Hi
I raised the issue with development team on this and once fixed it will update you here.
Meanwhile you can directly replace the covers as below path with same name
Male profile cover - components/com_community/assets/cover-male-default.png
Female profile cover - components/com_community/assets/cover-female-default.png
no gender cover -- components/com_community/assets/cover-undefined-default.png
Pages cover - /components/com_community/assets/cover-page-default.png
pages avatar - /components/com_community/assets/page.png
Male profile pic thumbnail - /components/com_community/assets/user-Male-thumb.png
FeMale profile pic thumbnail - /components/com_community/assets/user-Female-thumb.png