u/EnvironmentFew4651

I purchased my flight in early February for a trip I'm taking in June. With everything around fuel, I've been a bit on edge and checking my flight in the app regularly. Today, while just looking at the seating map because I wanted to see if there was anything more favorable as I'm flying with my 2-year-old, the entire seating map on three of the four flights (layovers) are all marked unavailable. I fly to see family every year and haven't been really loyal to a single airline, but even with that, I've never seen or at least noticed this before. Can anyone explain why this might be the case? Thank you!