I have a similar problem. I am flying with Mileage Plus since April this year. My flights are mostly LX. All my flights have credited automatically, except one with LH (IAD-FRA) where I had to mail the BP to UA. It was credited within 2 weeks.

Now I became 2P end of August. Since then none of my 6 LX flights since have credited automatically, although my FF# is correct on the BP. The BP even shows the new Status (UA*S).
I already called UA to ask what’s wrong with my account, but they told me it is active and I should claim the missing miles online.

Has somebody an idea what the problem here could be?