focus keyword not in url – hyphen problem

good day,

i think i could have discovered a bug: i am using rank math to optimize my seo performance. (switched from yoast)
i try to set the focus keyword like the title and the url of product.
as i am german speaking, i give you an example in my language:
“frühling – die jahreszeiten-kochschule” is the title of a product.
the problem seems to be the “space-hyphen-space” in the beginning of the title.
if i use spaces before the hyphen it will recognise the keyword in the headings and in the content of the post, but not in the url (error: “keyword was not found in url”)
if i change the keyword to “frühling-die jahreszeiten-kochschule” (without the spaces) then the keyword is found in the url, but of course not in the content or the headings.

i know for seo perhaps its no problem at all, but still it would be nice to get the scores within your plugin to a higher level and the optimization of posts to be “good” (green), while i try to implement all your suggestions. which is not possible, when these error occurs.

do you have any suggestions? thanks for your help!
kind regards