TD AmeriTrade: Cash Alternatives Redemption (MMDA1) 是什么？

以前都没注意，今天卖了股，觉得现金的增量不是卖股的钱，于是查看 transactions, 看到

TD AmeriTrade: Cash Alternatives Redemption (MMDA1)  deduct 350+

查了查网上：说是被借钱，会自动还回来吗？

What is MMDA1 cash alternative purchase?

Basically, they’re using your cash to generate income while you’re not using it. It’s what banks do with your deposits when you’re not looking. Call them. You can opt out. Although, it really makes no difference (on your end) whether you let them use it or not.