Can Botox or filler correct upper eyelid ptosis?

Hi - thank you for the question! Unfortunately ptosis cannot be corrected with wrinkle relaxers (Botox/Dysport/Xeomin) or filler. I cannot comment on your specific situation without a photo.
Subtle changes in brow position with wrinkle relaxers can improve the perceived appearance of lid symmetry. The more of your eyelid platform (place where you apply eyeshadow) is seen, the more “droopy” your eyelid appears. If you pull up on the eyebrow on the LESS droopy side & like this appearance, Botox may possibly help.
I recommend seeing your ptosis surgeon or someone very experienced with ptosis surgery.
Good luck from Boise, Idaho - Dr. Caroline Vargason @cveyeplastics

Nothing short of another operation will correct the residual asymmetry. However this is easier said than done. The fact that you have a minor asymmetry after your first operation is testament to the fact that this is a delicate operation where, in my experience, it is not always possible to get the two upper lids perfectly symmetrical... it may be best to cut your losses and live with it. If you find you can’t, at least you will approach any further intervention with your eyes open!