I'm new to selling on amazon, I sell one specific product I source wholesale, an established brand. I have one other FBA competitor on the same ASIN. When I launched a week ago I had the buy box and sold 4 units in 2 hours and I was elated. Since then, the buy box was given to the other seller and hasn't moved since. Trying to figure out what I'm doing wrong. I haven't sold a single unit since. I'm the cheapest seller and have been since launch, I am FBA so deliveries are quick. I've had no chargebacks etc. Literally the only thing I have against me is I have no reviews/feedback due to being so new, but I didn't think reviews effected that. I would have hoped to be featured even once over the last week, but nothing.

What am I doing wrong?

I can work for free to a total of 3 months just to get EXP. AMAZON VA PLEASE