Cannot make mortgage payments with app

I only have a mortgage through NYCB and as far as I can tell there is no way for me to make a payment to it from an external account. Therefore, this app is useless to me. Having to log in to the actual NYCB website is getting old and the features my two other banks offer in their apps (Navy Federal and USAA) are years ahead of NYCB.

RossCo. about Flagstar Mobile Banking