This is Tristan from Ziggicig HQ.
It will not cost anything to get the correct coil sent out to you and we will not request that you send the one you have back at your own expense. Could I ask, what coil you have received, was the resistance incorrect or was the coil model incorrect? Also, could you describe to me what issues you had with the service you received please as I would like the opportunity to try to get to the bottom of it for you.
If it helps, you could take a picture of the coil you received in error and send it to me at : tristan@ziggicig.com