Dealing with FBM replacement requests

Hi all,

After struggling with how to resolve this issue, and lots of research, I come to you for help.

Our customers sometimes request replacements, and oftentimes, the reason is that they need a different size, or something else which would be better suited by a return.

The customer did not mail the item back yet (the tracking number shows that the label was created, nothing else), but the replacement order was created and the ship by date is today.

I’ve seen in various forums that sellers request the customer initiate a return instead of a replacement, but how is that possible when you have 1 day to ship the replacement out, and most customers don’t answer Amazon emails?

Am I missing something?

It would be great if there was a way to turn off replacement requests altogether, but that does not appear to be an option.

Thanks in advance to any guidance provided here.