I have set up a LAMP application on my droplet

I have used my set DO ssh key which is the same used for my mac and my bitbucket account.

I install git and create a folder at the /var/www level.

CD into the folder and run my git clone command but get the following error

Warning: Permanently added the RSA host key for IP address ‘131.103.20.167’ to the list of known hosts.
Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

Any ideas how to fix this?
*ssh keys not my strong point