How can I change the address attributed to my iMac - it is listed as if it were at home close to me but not my home.

I have just set up a new iPhone and shortly afterwards received an Apple message that the 'Find My Device' app had been deleted. I then went in to restart it successfully but noticed that although the address for my iPhone was correct, the one for our iMac was not. It is for another 'Sheila' about a block and half away from us. How can I correct this?