Proman Products Renaissance Desktop Red Wood Book Rack Adjustable with Drawer, 24″ W x 8″ D x 12″ H, Reddish Walnut

Since my child has distance learning due to COVID, I purchased this to help organize cluttered desk. We just put it together today and it seems sturdy and a great organizer. When I bought it, I liked the feature of the drawer on the bottom to help keep things in reach, but not in the way. The only problem is there is ONE knob missing from the drawer. The knob was already in tact in the right side, but missing from the right. We looked all over and took the box apart and can’t find it. I’m not sure how to contact seller, so is there a way for me to get a KNOB sent to me?