Occasionally, you will ride across the large map to head to a side mission, you will get there, and the icon that was previously underneath your waypoint marker will have vanished. So, what’s the deal?
Red Dead Redemption 2 has a fully simulated world, so there are a handful of reasons why a quest giver might not be there when you eventually ride up.
The biggest reason is time of day. Some missions can only be triggered during the night, and some can only be triggered during the day.
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Another reason missions get locked out is when you’re caught committing crimes. To unlock them, you need to lose your wanted level, so ride out of the red area and lay low for a while.
It’s worth noting that some gangs might turn hostile towards you at certain parts of the story.
If a mission giver is in rival gang territory, it can be difficult to get to them without a confrontation, which can often draw the law. Be clever about your route towards them and you should be fine.