How do I stop my filler from migrating? (photos)

I have been having lip filler for about 6 years or so, I have had issues with filler being done badly in the past which has resulted in me having to get my lips dissolved and refilled on 4 separate occasions. I got them dissolved last year to start from scratch and then had 1ml in, see first picture. I then waited 7 months to have half a ml added and it seems to have migrated. The other half a ml was done about a month ago, no matter what I do or which doctors I go to the filler migrates