Stroke per side property missing

I am new to figma but I want to add strokes to only certain sides of a rectangle. I found the option and explanation on how to use it but that option but I cannot find this option at all. Any ideas where it is?
stroke property1

Thanks in advance

Most likely your object is not a rectangle or frame, so it’s not possible to add an individual stroke. Perhaps your object is a simple vector shape.

Yup that was my problem. Thanks for your help