What can I do to get rid of this sagging skin from by my mouth? (Photo)

Thank you for your question and photos. While you may feel that all of the swelling is gone I can assure you that from your photos and typical healing timeframe you have not reached your baseline which generally takes a minimum of 4 months. That said, I do not believe that your concerns will completely resolve even  after resolution of your healing process. The area you are concerned with doesn't appear to be lax skin but rather laxity of the deeper tissue which usually is addressed with SMAS work at the time of the facelift. This area can be very difficult to completely correct. Having three facelifts in 10 years is quite bit. I would wait and additional 2 months to see where things have settled and discuss options at that time with your surgeon. Further surgery may not correct this so be sure you are working with a board certified plastic surgeon whose practice focuses on facial aestheticsBest of LUCKDrG

It is still too early to determine your final result. You need an examination by an experienced facelift surgeon. It would be very helpful to know what technique of facelift was used (a procedure to address the SMAS would be very important). Also, it appears that you would benefit from volume addition in the areas of concern.