Twice having interviews at same firm/office

Two months ago I was invited at a big firm (JP Morgan) for interviews. They did like me but because the needs of the team changed, they decided to not hire anyone. One of the team members Peter, have I seen a couple of times during the interview process (first round and later) en had several phone calls with him.

Now I am invited for the firm (JPM) again but for another team/department at the same location. Should I let peter know that I will be at his office for interviews again soon. And if yes, what and how should I contact him (phone/mail?)? And what should I say in this email or phone call?

Thanks!