We present results of investigations on the correlated nature of electronic states crossing the Fermi level in Pb9Cu(PO4)6O (also referred to as LK-99) obtained within the DFT+DMFT approach. We found that the band structure in the vicinity of the Fermi level is formed by extremely narrow Cud states and p states of extra O weakly hybridized with each other. Coulomb correlations between Cud electrons open the band gap between Cu dxz/dyz and the extra-O p states that form the top of the valence band. Our conclusion is that the extra-oxygen p states play a significant role in the electronic properties and LK-99 cannot be mapped onto a two-band Hubbard model. We also conclude that doping with electrons will turn the stoichiometric Pb9Cu(PO4)6O into a metal, whereas the result of doping with holes is less certain. © 2023 American Physical Society.