Indigo Plan B option - does it really work? See Screenshot. Any Tips to book an alternative flight

My flight scheduled for February 2026 was rescheduled by Indigo around 15 days ago and I was provided with a link to reschedule the flight if I did not like the option given to me. I have been checking every day and I see this error every time when I try to pick an alternative flight.

Has anybody else faced this issue? Any way around? Thanks

https://preview.redd.it/dh07is1177ag1.png?width=1823&format=png&auto=webp&s=61e9069ad1c015432efb6c6c8bbd8f605bb925af