Hello, I ordered a SHEIN package (N°6A21592538375) which is marked as being delivered on July 31, I went to check my mailbox the next day but I did not find any package. I decided to ask Colissimo who confirmed that the letter carrier had put the package in the mailbox, and as I did not receive it they directed me to the carrier. We suspect that someone is stealing the packages in our building thanks to a key that opens each mailbox, but we don't know who it is. What am I supposed to do because I did not receive this package?

Hi I’m trying to find out where the package is today as the seller that I purchased it from said it shipped out on the 13/03/2025 and every time I tried to find out off the seller where it is they say that the carrier had lost it and they found it after 2 weeks went by so I thought that I would contact you directly as you are the carrier can you please let me know where it is and when you intend on sending it.
Thank you so much

Hello,
I am trying to find out where my package is. I have been tracking my package number AT661580438CN and the last date of any movement was April 25, 2025 which states it is in the US and passed customs. I have called USPS to try and track it and they tell me they can not track it with a China Post tracking number. Can you please tell me what carrier here in the US it was transferred to and the carrier's current tracking number.
If you can't help, is there anyone I can contact to locate my package? There has to be a way to find it.
Any help you can give me to track down my package would be greatly appreciated.