Less Fool, I 2014

A creature you touch becomes less susceptible to lies and magical influence. For the duration, other creatures have disadvantage on Charisma checks to influence the protected creature, and the creature has advantage on spells that cause it to become charmed or frightened.

If you cast this spell using a spell slot of 3rd level or higher, the duration is concentration, up to 1 hour. If you use a spell slot of 5th level or higher, the duration is 8 hours. If you use a spell slot of 7th level or higher, the duration is 24 hours. If you use a 9th level spell slot, the duration is 1 year. Using a spell slot of 5th level or higher grants a duration that doesn't require concentration.