13.56MHz antenna simulation HFSS(simulation results and actual results are differect)

Hi all
Thanks for your help.
I'm simulating a curve antenna under 13.56MHz . Thickness is 5um. Width is 76um.

practically, I measured the inductance is 5.5uH.

But the simulation result is 300uH with single lumped port.

I tried double lumped ports. The result is 54uH.

My settings are as follow:
solution frequency 13.56MHz
sweep type is interpolating.
frequency setup if 13MHz-14MHz 0.01MHz

There are two questions,
1.Should I set single lumped port or double lumped ports? why
2.By which method can I get about 5.5uH in simulation ?
thank you for your help