Personne n'a toujours tenté de m'escroquer sur la récompense.
"ne ... toujours pas" means "still not / not yet"
"ne ... pas toujours" means "not always"
In this specific sentence, though, the "pas" (which usually serves to distinguish between the two meanings) does not exist on account of the presence of the "personne". So how can I know without relying on the context whether this "toujours" means "still not" or "not always"?
Substituting "encore" would make things simpler, but what about if you insist on using "toujours"?
Personne n'a encore tenté de m'escroquer sur la récompense.