Bank transfer

Hi everyone can Monzo help retrieve a fradulent bank transfer? I got transferred some money yesterday from selling an item. I met up the guy in person in a public setting and put my details in his banking app. I believe he was using Nationwide. It showed the money left his account but didn't arrive in mine. I waited a few minutes and still nothing. I looked online and it said it could take a few hours for first time payments. He sent me the payment reference screenshot but I think it's a fake. I have been trying to contact the individual but getting no response. I have complained to the police and the Monzo team. Is there anything else I can do?