I just got a payout from a purchase 20+ days ago

I bought 2,638,157, and transferred it to my wallet immediately.

My payout today was 36,326

However, I expected 527,631 (assuming 20%)


BUT --- I am confused, because it came through as MINING  ... yet I am not mining, I just have my wallet open.



Anyway, what POS am I due from 2,638,157 (2.6 million)?