Do you really need a Copper Area or could you just use a round Top or Bottom Layer Pad and then close off the Solder Mask aperture by setting it to a value of -1.1*R where R is the radius of the pad as described elsewhere in other topics?

(-1*R works but -1.1*R guarantees no tiny area of exposed copper due to any rounding errors. )

Hi sir, I need a perfect round copper area. My pcb layout is not in circle shape. If I need a full of copper area no problem I make a any shape polygon to cover it. but I need a Perfect round shaped Copper area sir.

Sorry but in that case, I don't understand why you can't just use a round pad as I  described above.

Ohh sorry sir, Just now  I read properly.