I was going to ask a question on Stack Overflow, and start it like so:
One of these days I've run into an issue, where...
But then I thought, is this really okay to use Present Perfect with "one of these days"?
You're correct to think that this would sound odd; as a colloquial expression, the phrase "one of these days" means "at some time in the future." (Of course, there are circumstances in which the words "one of these days" can be used to mean something else, but it's clear that that isn't what you are asking about.)
I wonder if perhaps what you want to say is "I've recently run into an issue…"
Edit: As @TypeIA mentions in a comment, "in the last few days" or "in the past few days" would work, too – assuming the event to which you're referring is in fact that recent.