Hello,
You need to remove the border-radius that you defined via the settings of the Elementor (https://prnt.sc/hNKznLfKXpxn) and apply the circle style for the Shop’s buttons via Theme Settings -> Styles and Colors -> Buttons -> change the style for the “Shop buttons”.
https://monosnap.com/file/CmA3PIk1tqITGrrLUlNVGJwm4Qopkb
Also, there is the possibility to change the border-radius of the quantity (more detail in the below screenshot).
https://monosnap.com/file/Iq4xyIcAagp6znQG6RK3qs9uQZm5ov
You can also reach out to us if you have any questions.
Kind Regards