Hi @rajha,
Unfortunately, it looks like I cannot reproduce this issue on my side.
In the last update, all the BuddyPress templates that were in Gwangi have been moved over to our Grimlock for BuddyPress plugin.
However, this change shouldn’t have any effect on your child theme, as the template override still works the same way in this new version.
Please note that if you have enabled member covers, you need to override the cover-image-header.php file instead of member-header.php.
You can find and copy the original cover-image-header.php file from grimlock-buddypress/templates/members/single/cover-image-header.php in your plugins, then put it in your-child-theme/buddypress/members/single/cover-image-header.php in your child theme.
Hope this helps.
Regards,