That's one way to do it. Daytrade calls are confusing. Since you have a margin account, you exceeded your daytrade buying power. If you lost money on the position you took, with margin money, you have to pay the money back you borrowed to make the trade.
If you have the cash to settle the daytrade call, just wait on the transactions to post. Usually takes 2-3 days. If it wasn't your cash, you need to deposit 38k or sell your other position to cover the daytrade call.
Im kinda retarded, so take this with a grain of salt.