HOW CAN we make [ Co (NH3)4 CO3} carbonato tetra amino cobalt?

Answer 1

Carbonatotetraamminecobalt(III) bromide is referenced on the first site below (as CH12BrCoN4O3). It includes references.

An old method was to dissovle Co(III)CO3Br [anhydrous Cobalt (III) Carbonate Bromide] in liquid ammonia and then extract.