Why do I get a ‘Remote Management’ step when installing macOS?

I got a 2015 MacBook Pro from eBay. I’m trying to install Sierra from scratch (after completely formatting the SSD) but I get this strange extra step (although the install USB is vanilla and done using Apple’s own bootable usb tool) that I can’t pass (pressing continue asks me to connect to a IBM private network, which I obviously can’t do) Does anyone have any info about this. Where is this MacBook comming from? How can I disable this remote management step? Is this a custom firmwere, or where does this come from?