Corel Draw 2020 guide lines offset problem.

Hello,

i have an problem with guide lines. If i crate an 3 mm bleed margin for A4 (216x303 mm) and then return to the original size (210x297mm), so i see an offset. After this step the guide lines are not on the right position. Why? Is it an bug? In the vers. 2019 ist this not an problem.

I recorded an video to understand better this problem.

Video:

www.youtube.com/watch

Thanks for support and sorry for my bad english