Acne and Product Dilemma

Howdy, So awhile ago I had a really bad cluster of acne on one side of my chin, and it went any but still left a nasty scar. Now, I got a cluster of acne on the other side of my chin. However, I kind of wanted to add more onto my skin care routine, specifically I wanted to introduce Vitamin C and I also wanted to start using my Benton Snail Bee Essence after I use retinol and before I moisturize because I saw someone on here do that. So far I haven’t gotten break outs anywhere else on my face, yet the new “cluster” is still pretty ugly. I’ve used microneedle patches and regular patches to get rid of them ( I also did this for the previous cluster ). I have no clue though how these clusters have formed, since in the previous weeks I haven’t switched up my skincare routine. I am currently using a vitamin c serum I’ve gotten from a picky giveaway during my morning routine but I’ve been slowly introducing it and using it 2x a week. I was wondering if it was wise to add onto my skincare routine like this, or if I should wait until the “cluster” goes away, or just cover the “cluster” with acne patches. I also wanted to know if in general if it was wise to make these changes. I have oily, acne prone, sensitive skin and it’s getting colder, so my skin is getting dryer. I wanted to add the vitamin c serum to my morning routine and the essence to my nightly routine since my skin is getting dryer during the colder season, and also I need a ton of help fading scars. Let me know your thoughts! **Also just to clarify, I’ve been using the Snail Bee Essence for awhile now so my skin is pretty used to it, but before I was only using it during the mornings for about 3x per week.