Warband quests

Warband. i just got started back into WoW and wanted to backtrack and complete the other areas. I started in Shadowlands and it saying tht all my quests have been completed by my Warband, only in Maldraxxus…Went to Dragonflight and have gotten the samething all quest have been completed by Warband, but yet only into Ohn’ahranthis is for every quest on every Chapter except for Khaz Algar…Last time i fully sat and played for a long period was back in Legion. so is slightly confused why all this is like this?