iMessage and FaceTime doesn't work but Apple Store and iCloud does

I built a hackintosh last weekend. It's a Dell Inspiron 3567, Skylake notebook. I managed to get everything working just fine including QCA9565 Wi-Fi and sleeping on Big Sur. I couldn't generate a proper serial number tho. I put a MacBook9,1 SMBIOS for i3 6006u processor. My problem is, when I sign in to iCloud, it works fine but when I sign in to iMessage, first it seems like it's working, then it logs me off and says "an unknown error occurred." Is this expected?

I have no intentions to use iMessage and my legit account on this notebook, App Store and Apple Music is just enough for me and they don't seem to have any problem. Since I don't use my legit Apple ID for this build I don't mind if it gets banned or not later, so that's not a problem either. I followed the Opencore Vanilla guide as possible as I could. Hoping to get some answers..