man -k and man -f not working with pkgbase 15-stable installation

recently decided to give a try to 15-stable so i grabbed the alpha 1 disc1 iso and decided to go the pkgbase way, the installation went fine and smooth, finished the installation, rebooted into the freshly installed system, tried doing man -k dtrace, got "apropos: nothing appropriate" weird,  tried doing man -f dtrace, again got "whatis: nothing appropriate", tried the same with other manpages like "sh" and the other result was the same, at this point i startes the installer again and reinstalled 15-alpha1 but with "traditional installation" this time and man -k and man -f started working properly in that traditional installation system