What do you mean by "BOTH my own sending and the bill sending back to them? When did this happen, and from where?
My last cross-country return was in 2017 for a lens (sold and shipped from amazon) and I had to pay for the shipping myself to amazon.fr from italy. Didn't get a refund for the shipping cost, although the replacement arrived for free. Note that the lens was originally shipped to france. I was substituting for an identical item, which usually gets shipped right away. However, in this case, I had to wait for the return to be processed.
I had the same scenario in 2016, but from germany (shipped to germany, returned to france).
Note that I cannot complain for the service itself. I only had great experiences in return from amazon in general, but your description comes unexpected from me.
My last cross-country return was in 2017 for a lens (sold and shipped from amazon) and I had to pay for the shipping myself to amazon.fr from italy. Didn't get a refund for the shipping cost, although the replacement arrived for free. Note that the lens was originally shipped to france. I was substituting for an identical item, which usually gets shipped right away. However, in this case, I had to wait for the return to be processed.
I had the same scenario in 2016, but from germany (shipped to germany, returned to france).
Note that I cannot complain for the service itself. I only had great experiences in return from amazon in general, but your description comes unexpected from me.