I think I've been having same issue. Did your label look like this? Totally different from above.
Ordered 2 iPhone 14 Plus with trade in promotion from T-Mobile. This is the label I received. Since there was no logo I went to UPS first since the trade in I did for my 14 Pro had UPS label. UPS store said it was not their tracking # since all UPS tracking starts with 1Z. They tried scanning it anyway and said they had a few customers with same issue. I googled the tracking number and it shows it is a Fedex label going to Elk Grove. Go to Fedex and they tried to scan and it wouldn't work so they won't take it. I mention it is a Fedex tracking number and could they maybe just reprint label for me but they wouldn't do it. Made trip to USPS just for the hell of it and it doesn't work there as well.
Called Apple and all they would do is ship out new trade in kit. They couldn't just give me a new label to print myself. Wait a few days for new kit and it's the same darn label format again. Downloaded USPS/UPS/Fedex app since they all have barcode readers in app. None of the apps recognize any of the 3 barcode/QRs so I knew I was likely going to have issues again. Go to Fedex again. Same issue. Not recognized so they wouldn't take it or reprint working label. They say several people had same issue.
Tried PostNet next day. Third party shipping store that take packages for all shipping services UPS/Fedex/USPS/DHL/etc. Their system recognize it as Fedex. They took it and gave drop off receipt. Went on vacation. See no movement in tracking number for several days. I go back to store after and see it sitting on their counter. When Fedex came they couldn't get scanner to recognize labels so they wouldn't take it. Store had no way of contacting me and were waiting for me to just come back.
Tried going to Apple store. They can't bypass trade in kit. Called Apple again. Again they reissue trade in kit. But this time on one of the orders they reissued by first canceling trade in and then ordering new one. So now T-Mobile has removed my promo credits. I'll still try to send in phones but expect long uphill fight to get them to reinstate promo credits.
Finally, when I now scan the barcode with Fedex app it finally recognizes it. So I think their system finally recognize these barcodes. They released version 7.0 of app a week ago. Can't test it out until I received new labels since I don't think I'm suppose to send it in using old labels now that new shipping kit is coming.
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