  Recent theoretical studies have suggested that Kitaev physics and such
effects as formation of a mysterious spin-liquid state can be expected not only
in RuCl3 and iridates, but also in conventional $3d$ transition metal
compounds. Using DC and AC magnetometry, thermodynamic and $^{23}$Na nuclear
magnetic resonance measurements (NMR) we studied such a candidate material
Na3Co2SbO6. A full phase diagram of Na3Co2SbO6 in a wide range of magnetic
fields and temperatures is presented. The results demonstrate transformation of
the antiferromagnetic structure under the external magnetic field, gradual
development of the saturation phase, as well as evidence of gapped behavior in
certain parts of the phase diagram
