My wife wants to order food that is 100% kosher for passover from an online retailer. We ordered before and sometimes they substitute one item for another. If i order now for delivery on chol hamoed or order on chol hamoed for mext day delivery, Im afraid maybe they will substitute a kosher for passover item for something that is not kosher for passover or worse maybe ship me someone else order or include items that are not kosher for passover. If i do get something that i did NOT order that is not kosher for passover, can i return it to the seller for a refund or do i need to burn it on chol hamoed.
You can’t acquire it on Pesach. One is not even supposed to handle Chametz that isn’t his on Pesach. You can refuse to accept the order or have in mind not to acquire any Chametz, and you can request a refund.
If it’s likely that this will happen, I would suggest avoiding this situation if possible.