Reserves of Strength + Warlock Invocations

[Yogibear41]

Multiclass spell caster that also has warlock levels for buff invocations, already have the feat reserves of strength for my normal spells in certain situations.

Can I use Reserves of strength with my 24 hour buff invocations to make them harder to dispel?

[Troacctid]

No, because it only works on spells, and invocations are not spells.