«git clone git://mywikiname.branchable.com/» gives «fatal: remote error: access denied or repository not exported: /». I already added SSH key. How do I troubleshoot this, please?
ssh keys are not relevant when using a git:// url.
If you want to clone using ssh, there's a different url for that.
Branchable sites only support git:// urls when they are configured to let
anyone check them out, which is configured by the branchable setting,
which shows up in the site's web configuration page as "Allow anyone to
branch, check out, and copy this site?"
This is enabled by default for sites hosted on branchable, so I guess it
must be turned off on your site.