Not sure where to put this, but I'm still a relatively new player so here we go.

I have a retainer I want to be a miner, but I hadn't started miner yet so I picked it up real quick so I could make my retainer a miner as well. I sent her on 2 ventures before I noticed she's not leveling up, and her "max level" for miner is 1. Thinking it mirrored mine, I went out and got mining to level 7 (and did my level 5 quest) on my character. But her max level is STILL 1.

My BTN is 50, and my BTN retainer's max level is 50. So what has to happen to make my mining retainer's max level go up?