Is it possible to dissolve only a bit filler, not all?

Hi, as long as it is a hyaluronic acid filler, you can dissolve the filler with hyaluronidase. There is an art to doing this. You can dilute the enzyme and/or use a very fine needle and precisely dissolve the areas where you have too much filler. If it is not done carefully, there is a risk that all of the fillers will dissolve away and even your own hyaluronic acid can be removed leaving you with deflated wrinkles that can last for quite a while. I would make sure the injector has experience doing this or find someone who does. 

At this point 4 days after your treatment, you may still be seeing some swelling from the actually injections themselves so I would give your face a little more time to recover before judging your results. With regards to hyaluronidase, it is certainly possible to dissolve HA filler using hyaluronidase. However, its not possible to predict how much of the filler will remain. You can also start with a small amount of hyalurondiase and keep adding more until you get to where you want to be. The alternative is to have all the filler dissolved and start from scratch with another injector. 

Hello - expert placement of hyaluronidase into areas which had previously been injected with hyaluronic acid fillers will result in dissolution of that filler. The degree of dissolving depends on certain factors: exact placement into areas of previously injected filler, skin thickness, any scarring in the underlying tissue, etc... Small, controlled amounts of hyaluronidase can safely remove some of the filler, and results are evident quite quickly. I would recommend seeing a physician injector who knows facial anatomy exceptionally well, like a facial plastic surgeon. 
Best - Dr. Singleton