Sometimes Nintendo64 Game Packs don't run at first try when powering (for whatever reason).
Recently I had this situation with one game, and remembering the times when that console came out I recall perfectly that a common "fix" or procedure that was known to work was to take it out and blow some air on the connectors before re-inserting. This was, as I remember, widely known and used across gamers I knew/know.
I wonder if this is actually recommended procedure for such situation, or if the blowing ever helped or if it was another thing that did the trick.
My intuition now says that this may work but also may not be a brilliant idea, but I wonder if there was a reason why that may have been a thing once.