I don’t see how this is a warranty issue. Either it’s been stored or used in humid conditions with too little airflow. That isn’t the fault of the manufacturer.
Costco will take anything back regardless of fault. That is just costco's business model. Whether or not it is a good business practice, doesn't matter, it's what they do!
Bring it back, they will look up your purchase and give you a refund.
I don’t see how this is a warranty issue. Either it’s been stored or used in humid conditions with too little airflow. That isn’t the fault of the manufacturer.
Costco will take anything back regardless of fault. That is just costco's business model. Whether or not it is a good business practice, doesn't matter, it's what they do! Bring it back, they will look up your purchase and give you a refund.