Indentations on corners of mouth after lip filler, how can I fix it? (Photos)

I just had 0.5ml of lip filler. I’ve done only 0.5 for the past 3 years, approximately once a year, as I find that this is sufficient for me. The last two times I noticed an indentation at the corner of my upper lips. I didn’t have this the first time I did lip filler - and I had had 1ml then. The photo with make is the old one from my first lip filler ever, for comparison. Is it the placement of the filler that caused this? How can I fix it?