Transfer Apple Watch activity

My daughter just got a new iPhone 11 and her Apple Watch activity did not transfer with the rest of her phones data. The transfer from her old phone to the new did not go smoothly, but it got done, then the re-pairing of the watch did not go as hoped either, and we did a hard reset of the watch to get it to pair, then when it synced most of the activity did not sync. Any ideas how to transfer the data from the old phone (it appears to still be there)?