I was wondering if someone more seasoned can help me out here.

April of 2022, I booked award flights through Turkish Airlines on UA metal. Flying ORD to KOA. Used 45k miles transferred from Cap1.

Original booking was Non-stop in both directions.

UA 66 on Feb. 25, 2023. ORD-KOA
and
UA67 on Mar. 5, 2023. KOA-ORD

Reservation was confirmed and ticketed. I have a TA reference number, a UA reference number and 3 TA e-Ticket numbers.
Checking my reservations on UA's website showed they changed/canceled the non-stop return. The UA reservation shows it replaced with an acceptable 2 segment itinerary.

UA643 KOA-SFO
and
UA2056 SFO-ORD.

UA says the ticket needs to be reissued, so I called TA to have it reissued and they are saying that can't reissue it with the flights that UA has put in place. They only show options that are either a few days earlier or a few days later. I have called multiple times and either gotten this response, or 'call back tomorrow and see what is available then'

Am I screwed on this? 8 months ago I had flexibility in my dates. Less than 2 weeks out now, I don't have the same flexibility. Is there anyway to get UA to release those flights they put on my reservation so TA can book them?

Thanks for any help!