The New York Stock Exchange warned Flagstar Bank (FBC) of a possible delisting as its stock traded below $1 per share for 30 consecutive days. The Troy, Mich.-based bank must push stock shares above $1 by Feb. 18, 2012, in order to avoid any action, according to NYSE policy. The bank alerted investors to the warning on Wednesday. Flagstar held $12.7 billion in assets as of the end of June. In the second quarter, the bank narrowed its losses to $31.7 million from $81.9 million one year ago. Flagstar hasn’t reported a profit since the second quarter of 2008. Since the financial crisis, the bank has been unloading nonperforming mortgages, dumping $474 million in loans in November and another $80.3 million in the first quarter. It also sold its bank franchise in Indiana, netting $23 million on the sale of 22 retail branches. Write to Jon Prior. Follow him on Twitter @JonAPrior