Minecraft no longer saving secondary players in split screen

My wife often play minecraft with me on the same tv using Xbox series x. When we use split screen, they always create the world under our main xbox live account. Then she logs in via her own xbox live account. When she used to play, secondary players would also start out with a map just like the host. And when done, it would save her progress and inventory. Now, though, secondary players dont get a map. The worst part is, if we save/quit and then try to return later using the same process, the characters have reset. They return to the original spawn, despite having slept in a bed and the character's inventory and XP are reset to nothing. Why is this happening? Please help me fix this!