Circular printing issue with Da Vinci Jr 1.0 3in1

[Diavolucci]

Hi,

I am completely a newbie on 3d printing. I have recently got a XYZprinting Da Vinci Jr. 1.0 3in1 printer. After spending hours on the settings I am somewhat comfortable with the outcome, however there is one item that I cannot seem to fix. When I print any circular item, there are two points top left and bottom right that seem to be offset somehow and I am getting a somewhat oval shape printed. This seems to be from the moving print bed when it reaches its extremities on the y axis and the print head is moving on its z axis.

Is there some settings I can use / modify to try and minimise this issue? I attach a photo to illustrate the issue.
Any help would be SOO MUCH appreciated.

Best regards

Roberto