Cant able to select magnetic field to spiral coil

Dear all,
I made a geometry of spiral coil considering inner radius of helix is zero and when i am defining the material to coil, its not able to take in domain. It is taking in edge and then when i am defining magnetic field using single/multiturn coil domain am not able select and define the parameters. Please let me know what is problem ?
Thanks


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kishore Naik Mude