Sending a bag back
Unopened bags
Return through the same order. The store issues the label and the refund.
Torn or damaged on arrival
Photograph the box and the bag before you clean up, then report it on your order page — that is what the store needs to replace it.
Opened substrate
Wet Bio-Substrate is living and can't be resold once opened. If it arrived dry or leaking, report it right away.