FT購買美股問題 - 理財

大家好
小弟第一次使用ＦＴ以及買美國股票
昨天入金美金5000今天開盤前用市價買了些股票
結果總購買金額超過5000

我的帳戶結餘目前顯示如下
現金結餘 -$155.02

我只要明天有入金不要變負數就可以了是吧？
需要付利息的費用嗎？這種情形通常有幾天的緩衝呢？

>>自問自答一下
剛收到ＦＴ的信：

Dear Firstrade Customer,

The recent purchase of securities or fees assessed in your Firstrade account
has created a cash call. If this call is not met within the time required by
Regulation T, per Federal Reserve Board, portions of your portfolio may be sold to cover this cash call.

Your current cash call is as follows:
Account No.: ###-##xxx
Due Date: 03/27/2020
Amount of Cash Call: $155.02

看來就是ＦＴ先墊了，今天入金了應該明天會入帳吧.....

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