Update existing lead from subscription center

[dannylearmont]

Hi, I'm new to Marketo so I'm still trying to figure things out.

I've imported the OP-Preference Center v3 program from the Marketo Program Library to help me get started but I'm having some issues.

I've updated the unsubscribe HTML in Admin so that it directs recipients to the preference center when 'unsubscribe' is clicked in an email. 

When the link is clicked, it successfully takes you to the preference center. However when the form is submitted, a new lead is created in Marketo rather than updating the existing lead. Is this expected behaviour?

[Katja_Keesom]

Did you actually send the email address to yourself as a real email send? The link tracking doesn't work with sample emails...