I accidentally made a few trades totaling about $6,000 in my Roth IRA that I intended to make in my taxable account. I realized the mistake when I got a notice from from broker asking me to deposit money in my account.
I immediately sold the shares and an equivalent amount of another stock because it's something, but the cash from those sales won't be deposited before the previous trades settle. I'd deposit the amount I owe, but my 2018 MAGI is too high to be eligible, and I owe slightly more than the contribution limit covers.
My Roth IRA is entirely invested, hence my problem. I think I'm allowed to have a negative balance on IRAs because my taxable account is a margin account (like it's a bug in the system), but I could be wrong.
What are my options to make the brokerage happy? I'd happily pay the margin interest for three days, but I don't think that's how this works. Are there any legal concerns?