A required conversation was missed
A major event may unlock another interaction rather than immediately starting the next objective. Revisit the people or places directly connected to the last event.
The correct place was visited at the wrong time
Being in the right location is not always enough. Some events depend on when the location is checked.
A prerequisite was never completed
An earlier task or item may quietly gate the next step. Review recent objectives rather than searching the entire game world.
Too many tests were mixed together
If you change several things at once, a successful result does not tell you which condition mattered. Return to a known state and isolate the test.
A good save was overwritten
Progression troubleshooting should not risk the only working save. Preserve a backup before experiments that could alter game state.