A fired telemarketer fakes the paperwork to become a family physician. When her patients start to see through the lie, she realizes she’s in the perfect position to silence them.

The first sentence seams more of a backstory than part of the central plot and could be cut all together from the logline.

Other wise the wording is off, for example: “…her patients start to see through the lie…” her patients don’t “start” to do anything rather they either do or don’t find out she is lying.
“…she realizes she?s in the perfect position to silence them…” is a long winded way of saying she must kill her patients, the compelling aspect of the forward motion nature a plot gets from a clearly driven character pursuing a goal is vital for a good story in film.? Define her goal and make her her chase it with all her might.

A suggestion:
After her patients discover she faked her medical qualification certificates a doctor must silence them before they alert the authorities.

Presumably the MC will kill off the patients with medicine or surgery once she realizes they are on to her. The problem with this logline is the basic logic on which it relies; if her patients don’t trust her why would they take the medicine she prescribes or undergo the surgery she recommends?

Lastly this is a story with an anti hero and therefore needs some sort of redeeming quality to her other wise why would the audience care about a con artist who kills people to protect herself?

Hope this helps.