I am able to commit changes from source tree but I get "Permission denied" error. I suspect it is a password issue but in that case I shouldn't have been able to commit as well.
Any idea what might be the resolution for this issue ?
It seems you had your repository under the HTTPS protocol and once you set the URL origin your repository became to connect under the SSH protocol. Would be possible to generate a key-pair, add the public key to your Bitbucket repository and the private key to your ssh and give it a try.