import goods

 all Respected expert Sir.

   my gst registred client import a machine amount 1700 dolar Rs.aprox 1.16 lac. port agent paid custom duty & igst aprox 4000 cvd & igst 3200 . client paid to agent
but item gst rate 18 % agent paid less igst . what's solution this mater 
what's will be pay difference igst by client & how claim input