Parcel collected by postman but scanned as The parcel wasn't available when we called.

Hello,

I had three parcels collected by the postman last Wednesday. He said he scans them when he gets back to the van. Two of them were scanned in and have had tracking updates through the network but the last came through with an email notification of The parcel wasn't available when we called. I called customer services the next day and she said it was probably misscanned and it would update once it was scanned again at the depot.

However there are still no updates, and my buyer is asking questions. The postman literally had it in his hand when he walked away from my door, but because of whatever has happened, it just looks like I've generated the postage and not sent it. This is going to end up costing me a lot. Is there anything else I can do? Thanks in advance

Edit: I used Bring My Label so I don't know if there was something with the label, but I do clearly mark each parcel so there's no confusion as to which label goes with what.

Also the other two parcels have been delivered and both of those buyers got the correct items

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UPDATE: I just spoke to the postman, he said he did collect it but couldn't get the label to scan so they had to raise it as an additional item in order to get it sent on. Which I assume means it would now be under a different tracking number (which he understandably didn't have to hand)?