Unknown said:

hope this makes sense

Not really? but anyway:

If you have the item you only sell, set up in the sell item's Bill of Materials as composed of 1 each, of two other items that you only buy, and 'build' 50 to sell, Sage 50 will:

1. Take 50 each of the two bought items out of stock.

2. Add any 'build' costs set up in the Bill of Materials tab

3. Add 50 of the item to sell, into inventory.

If you skip the 'build' step, and go straight to selling the item, Sage 50 will offer to 'build' the items before:

4.  Take 50 of the item to sell, out of inventory, and record the cost-of-goods-sold.

Unknown said:

how do i fix this!?!?!?!?!?!?!

With an Inventory Adjustment.  There is no 'undo' or 'correct' for a Bill of Materials or Build from Item Assembly transaction.