Dear Customer, thank you for contacting Firmoo. There is no minimum PD and the frame size is the one that matters. Due to the size of the frame S0121R
(lens size) in combination with your PD measurements, the lens would not be cut out properly and we need to use a special lens to fit your vision needs. If you don't want to pay an extra $10 for the special lens, we suggest you choose a smaller frame. Please check your old frame size and filter the frame size from our website for better reference. We understand that choosing a perfect frame size online can be tough sometimes so we suggest that you could please check this link https://www.firmoo.com/help-p-1.shtml
for reference. For any further questions or immediate assistance, you may also call our call center thru toll-free hotline at 1-855-487-6006 opens every day from 7 a.m.- 4 p.m. PDT. You can also contact us through our Live Chat Support Team: Start a live chat (Everyday, 3 a.m.- 12-midnight PDT.) or email us at firstname.lastname@example.org. Please stay safe and healthy!