Running out of content despite having -> END at the end of the knot

[xlomid]

Hi! I'm new to Ink and have found it a really cool tool so far. However, I am baffled by the "Ran out of content warning" I keep getting in one of the dialogue knots:

=== Go ===
{not offeredHelp:
 Pray do. But unless you develop a more inquisitive mind, you may only be able to get so far.
 }
{offeredHelp and not usedCrystal and not reminderCrystal:
~ reminderCrystal = true
Oh, and do make use of that crystal to visit Student. You will probably need his help to get past the gate too.
}
{offeredHelp and (usedCrystal or reminderCrystal):
{cycle:
- Good day.
- Yes, yes, begone now.
- I shall see you later, possibly.
}
}
* {offeredHelp and not usedCrystal and not reminderCrystal} [Who's Student?] -> Student
-> END

I originally had everything within a single nested condition with else statements etc., but first the choice didn't appear and then the warning started coming up. So I rewrote it as three separate conditions, and it still doesn't go away. However, when I remove the part in the second condition that assigns a variable (~ reminderCrystal = true), everything seems to work just fine.

Any suggestions and guidance would be much appreciated.