Cannot draw perfect circle in after effect 2020 cc

[#1]

Hi all. I'm using after effect 2020 cc. I created a composition in 1080x1080. I fail to draw perfect circle even I hold "shift" key.. The number is shown as it IS a circle, but still it is just an OVAL. Could anyone tell me what goes wrong..?

[#2]

Hi all. I'm using after effect 2020 cc. I created a composition in 1080x1080. I fail to draw perfect circle even I hold "shift" key.. The number is shown as it IS a circle, but still it is just an OVAL. Could anyone tell me what goes wrong..?

[#3]

Check your composition pixel aspect ratio.

Mylenium

[#4]

the problem is solved when I changed it to square pixels. Thank you!  

[#5]

can you please tell me how you fixed it