/%post-name%.html and category and single post comment trailing slash problem

i have setup permalink to /%post-name%.html in my website.
every thing is working well as it is.
my theme has a single category feed links and also single post comment feed links.

now when ever i click on these feed links i struck with 404 error. webmaster tools as a list of all these 404 error pages.

ie : https://www.mystie.com/categoryfeed (404)
https://www.mysite.com/post-name.htmlfeed (404)

i do not want to change my permalink settings.

any help ??? or Tips !!!