According to werner theory primary, secondary of central atom in  CoNH36Cl3 Complex respectively

3Cl- satisfies primary valency, 6NH3satisfies secondary valency and the ligand satisfy primary and secondary valency is called duel valency. that means ligand involved in calculation of primary and secondary valency. Hence no such type ligand in given complex CoNH36Cl3 , so duel valency  ofCoNH36Cl3 Complex is 0