What went wrong with my deep plane lip lift? 9 months post op. (photos)

Thank you for showing your photos and sharing your questions. So sorry to hear you've been dealing with this issue. It's difficult to say for sure what the issue is without being able to see how the lip moves. For such a simple procedure, lip lifting carries a risk of complications and healing issues that is not low. If it's not done perfectly (or close to perfect), complications can occur. The scar is noticeable because it is widened. This can sometimes happen if there is tension on the wound while healing or if deep sutures weren't placed appropriately. There is some asymmetry (which was also present in your preop photos). This can sometime be exacerbated by shortening the lip. I'm not sure what is meant by the term "deep plane" lip lift. Lip lifting is generally a skin and subcutaneous operation, no involving any dissection or surgery underneath the muscle of the lip. Consider giving the healing process another 3-6 months and then consult with a board certified plastic surgeon or facial plastic surgeon that has done a lot of lip lifting to see what options might be available. Unfortunately, an in person visit will be necessary to give advice beyond this. I wish you the best and hope that things work out for you. Kind regards,
Dr. Harmych