I booked a flight on UA.com from EWR-MNL and it is a UA flight EWR-NRT and an ANA flight from NRT-MNL. I have flown this route many times without issue. For the first time I changed the day of my flight by 1 day on UA.com. The flights show up on the website no problem and all seemed good. When I go to book my seats on ANA on their website I noticed they have 2 separate reservations for me, one for the new date I booked to leave earlier from EWR, but the return flight is not there (there was a new PNR for ANA created when I changed the flight). The problem is the return flight did not show up. Sure enough when I pull up the original PNR it shows both my original NRT-MNL and MNL-NRT flights. So basically I have 3 flights now booked on ANA and I am concerned when I do not show up for the originally booked NRT-MNL flight (because i will be taking that flight on a different day with newly changed ticket) they will cancel the return MNL-NRT flight and I will be stuck. I called ANA and they said it is UA's problem because they ticketed it and I call UA and they say it is ANA who has to fix it because it is their flight. I am so confused about how to fix this, any suggestions???