I had fillers for Marionette lines, about 5 years ago. It cost £700 over 2 appointments, and I was thrilled with the results, which lasted a couple of years ago. It was done at a cosmetic surgery clinic, in the city centre.
Last year, the lines were particularly bad, as I'd been on a ventilator for 2 weeks, and the marks were really ingrained. I paid £200, for one appointment, at my local pharmacy, last November. I was pleased for a few days but then noticed that where the lines had been filled, there were white scars (like stretch marks) in the place of the lines. This has worsened, and the man who did the fillers advised me to massage the area, daily, he said the white scars were "just the fillers showing through the skin" Absolute tosh. I'm now line-free but instead have quite obvious white scars.
Go to someone reputable, and get some recommendations, if possible.