Multiple NPCs Missing For Quests?

So I’ve been trying to do the quests in TWW expansion and it looks like I have several NPCs missing that I either can’t get the quests from or I can’t turn them in. This has impacted the campaign quests, several of the regular quests and even the Siren Isle quest. I’m pretty much locked out from progressing anything since I can’t finish any of those quests.

Has anyone gone through this previously or know if there is something possibly wrong with my client?

Could you be a bit more specific?

Which quests and/or NPCs?

Same thing here - finish quest line and then the end NPC isn;t where it supposed to be (Alysa Cloudsinger should be in Stormwind for turn-in, but isn’t) and The Bronzebeard Family isn’t in Dalaran to continue that quest line.
And this isn’t the only two - frustrating.
Can’t finish the quests to get to the expansion part - really sucks.
Did all Bliz recommended and still no relief. They know how to kill the enjoyment of the game.

Stormwind Quests tend to get messed up by multiple instances of phasing based on whether your character has done certain expac launch quests or not.