I would need more information to be able to give you a more precise answer but I will try. First, did you have an upper eyelid surgery (Blepharoplasty) at the same time as the Facelift? if you did, maybe too much skin was removed but in that case you should be able to blink but not to close your eyelid entirely.
If you only had a Facelift, then does your left forehead move, meaning are you able to raise your left eyebrow? if you cannot then it is possible that one of the branch of the facial nerve got stretched during the surgery and became weak (neurapraxia). Such event is rare but if it does happen it usually resolve in a few month. Your surgeon may decide to put you on steroid to decrease the inflammation and help speed up the recovery of the nerve. Meanwhile make sure you are using artificial tears during the day to moisten your eye and thick night eye drops.