Documents needed for Pesel Number (Kraków)

Hello everyone,
I have been living in Krakow for 7 months now (I am from Italy) and I really have to applied for a PESEL no. My company gave me the instructions on how to do it, but it's stated that I need my flat renting contract. I do have it, but it's not on my name, but on my boyfriend's name. Do you know if that will be a problem and how I could act in this case?
Thank you in advance for your help
Sara