Amazon return chaos!

I have logged a return with Amazon for an item purchased from them. The return was approved and collected but never got to the seller. Eventually it was returned to me.

I got in touch with customer service to enquire about the situation and what was going on. Also wanted to find out about next steps and way forward. Since then I have been in touch with them 3 times. There seems to be no clear process in place for this type of situation, and I still have the item with me.

At this point, it has been suggested that I send the item back to the seller at my own cost, and hope that it does get to the right place. Also hope that the refund is processed with no issue.

I'm not comfortable with this, since it is completely outside of their process, and there are too many points where everything will go wrong. Then I'll be left with no item, no refund, plus the cost of the return...