Linking Bitbucket commit to YouTrack issue

Hi,

I'm trying to link a commit on bitbucket to an issue in YouTrack but I'm getting a warning triangle as follows:

Both the YouTrack user and the bitbucket user email addresses are the same, I've changed the 'Full name' of the user to the name shown above too but still it doesn't seem to find the user in YouTrack. How do I go about adding the VCS user name to the Hub account as mentioned in the dialogue above?

Ideally step by step instructions please!

Many thanks

Kevin