Retoure not yet paid back

Hi, I have been a client of yours for ages, without any problems. Until recently.
I ordered a few pants for my husband on 4 Sept 2023 (862269450), it took a few days to arrive, and i sent the not needed ones back on the 2 October 2023.
On 9 December 2023 I got a mail from you that my return was too late and it was not accepted, so you are sending it back.
I wrote to the customer service who acknowledged the mistake, and requested that once i get the package, i should send it back.
The package Nr 26354172302713 arrived, and as requested, i sent it back, with the tracking Nr 70346172006747 (I dropped it off at the Hermes drop off point in KIOSK AM MIERENDORFP, Mierendorffpl. 3, 10589 Berlin.) Since then i have not received any money back. To my requests i just get the same irrelevant responses from the customer service. Today i received an email that asks me to confirm that i did not receive the package Nr 26354172302713....

How can i explain that i did receive it, and i sent it back again?

I am really fed up already and am considering what steps i can take to get my money back and close this topic finally.

Kind regards,
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