Juvederm for Acne Scars Left Skin with Bumpy Appearance - is This Common?

It sounds like your acne scars were "overfilled".  It does not take much product to lift the depressions especially if you subsize them first. You can consider Vitrase if you don't want to wait for the Juvederm to breakdown. You might also want to consider CO2 laser resurfacing which can improve skin irregularities from acne scarring.

I'm sorry to hear that you've had to experience this. It is unusual for bumps to remain for so many months after your treatment. I'm wondering if it is excess filler that can be dissolved with hyaluronidase, or if you have scar tissue. I would suggest you return to your injector for an assessment.

Injecting acne scars is not an easy situation because of the chronic scar tissue that is there. So some lumpiness is not unusual.

When injecting acne scars with fillers, it is helpful to do some subcision first with the needle to free up the adhesions and create a little pocket for the filler.  This helps to avoid the risk of getting a doughnut effect where the filler fills around the scar and the scar stays bound down.  Also, it helps to dilute the filler with lidocaine and inject slowly so that the filler lifts up the scar.  I agree that filler is most useful for deeper scars and laser treatment and/or microneedling is more useful for the surface scars.

Acne scarring is near and dear to my heart, as I have dealt with my own as well. I use fillers for the deeper scarring quite a bit, and it can be quite useful. For more shallow surface irregularities, skin resurfacing is usually most useful. Most commonly, patients require some component of both to get the best results.

Dealing with the acne scars can be a process - they did not happen overnight (well, each one may have, but you get the idea...), and they are not corrected in one treatment most of the time. If you have lumps, show them to your injector and see what the options are to make it better - does some need to be dissolved, can it be punctured and expressed if there is a little collection there? As the correction was done with Juvederm, it will eventually go away if you do nothing. But, by showing your injector what is going on they can help you get better faster, and hopefully help you find the modality that will help you achieve  improvement that you are looking for.