Lest there be any doubt, affixing something has absolutely nothing to do with repairing it. I know it sounds like it should, but it doesn’t
To affix something means to attach it. That’s true whether the thing being attached is broken and in need of fixing or not. But affix is a fairly common word, so you probably already knew that. If not, you’re welcome. I’m glad I could help.
I didn’t know until just now that affix also has a noun meaning. To grammarians, an affix is something that is added to a word to create a derivative of it with a different meaning. In this sense of the word affix, suffixes, prefixes and infixes are subsets of affixes, with a suffix being added at the end of the word, a prefix added at the beginning, and an infix being added in the middle.
So now you know. You may still not care, but at least now you know.