How Do I Contact A Seller That Doesn’t Read Messages From Their Inbox?

I recently just received the wrong item in the mail and requested a return but for a replacement with the right item instead of a refund. The seller messaged me back with shipping label and directions on how to return it but there’s disclaimer at the bottom of the message that the seller doesn’t read the messages and that all messages are automated. Maybe I’m just overthinking it but I’m worried that they probably didn’t see my request for a replacement instead if the refund. I know replacements are part of their return policy because I look at the return policy every time I order something.