So i'm doing the quest where you go around collecting water on the Forgotten Vale, collected 4 of the 5 ponds of water and decided to go make some sidequests of the dawnguard...the one where you rescue a priest of Arkay and convince him to join you to be precise.
after that, I wandered around skyrim until I found a mine that was infested with Draugr and the townsfolk asked me to clean it. (up to this point, Serena is following me)

Well, entered the cave, finished the quest of killing all Draugr and when I got out, Serena wasn't following me. I return to the Mine and she's there standing like an idiot. I can still command here to "wait there" and I brought her to the entrance of the Mine but she wont go out.

She just stands there, talks as if she was a follower but she wont follow me around.

Can I fix this? If I resume the main quest and enter the inner sanctum will she appear with me?

When that happened to me i waited a few hours and she returned back to me.

Make sure you don't have any garlic in your inventory

Sometimes when she gets stuck I give her a good "shouting" and she will move...

waited 24 hrs outside and inside the mine, and nothing happened...she just stands there.


ate all my garlic, shouted ay her a bazillion times and nothing.