My chin implant was placed too high, is mental nerve damage possible? (Photos)

You may have some weakness of your left lower lip which can occur if the marginal mandibular nerve is stretched. Are you noting gradual improved symmetry and movement of your lower lip? Nearly all lower lip weaknesses after chin implant get better within a maximum of 5-6 months postoperative.
If your implant is misaligned and causing chronic discomfort, it may require removal. Sometimes what patients feel as a misaligned implant ends up being asymmetrical swelling. If you are not comfortable with your surgeon's advice, consider getting a second opinion - digital images do not substitute for an examination. Wishing you well. Dr Joseph