It does not have the power to "lift" an eyelid no matter what was promised to you. It is not really a nonsurgical eyelid lift. Generally eyelid issues are best addressed with eyelid surgery. Consider posting a photograph here so we have a better idea of your issues.
Plexr is a non-invasive technique.
In general the lesser invasive, the less is lasts.
More invasive techniques tend to last longer.
Thank you for your question. Plexr is a temporary solution and is not engineered to provide significant changes to your appearance. I suggest that you consult with a board certified facial plastic surgeon to discuss the benefits of eyelid surgery, known as blepharoplasty.