The tracking app
The brand said one thing and the tracking app said another, which for a company whose product is the delivery itself is a real problem rather than a cosmetic one. A single "change delivery" action was carrying too many scenarios and fell apart on edge cases like several parcels going to one address, and delivery information had no hierarchy, so everything looked equally important. Support absorbed the cost of it, and their tickets were most of the evidence, alongside an audit of the app, a competitive review, and testing with early users.
The main move was structural. We introduced shipments as a layer above individual parcels, so several parcels to one address became one thing with parts. Once that existed the rest got simpler: actions could be separated instead of stacked into one, information could be grouped and progressively disclosed, and delivery status could say what it meant. Three weeks, and an active service we couldn't disrupt, so we went for a minimum viable experience rather than a polished one.
The old system only knew about parcels, so it had no way to describe a delivery of several. Once it did, most of the confusion resolved itself. A lot of interface complexity turns out to be a missing concept rather than a layout problem.
Where it was heading
Alongside the MVP I worked up concept screens showing where the experience could end up once the patterns were settled. They weren't built, and weren't meant to be yet. Shipping something deliberately minimal is a much easier argument to make when people can see what it's making room for.