In reply to prashanth.billava:
In the top_tb you have to make an instance of the VIP interface like this:
X xif(); // don’t miss the brackets!
Furthermore you have tp pass this interface to the uvm_config_db in the initial block of the top_tb:
initial begin
…
uvm_config_db #(X)::set(null, “*”, V_IF_CHIP, xif);
…
end