Komga requires valid URLs for the links field, but Komf does not seem to ensure that the URLs it parses are valid before submitting them to Komga.
here is the log.
komf error log.txt
in case the URL has been fixed by the time you get to this, this is the link that broke it (on mangadex, for official English)
htttps://www.alpha-manga.com/manga/121000501
I don't think it is possible to always fix broken URLs, so it would probably make sense to validate the URL with a regex (or preferably a library function if one exists) and not submit it to Komga if it fails.