Miracles are, by definition, impossible.
Think about this:
God is all knowing, all powerful, all good, and perfect.
A "miracle" would mean he literally changes his big universal plan for you.
If he "changes" his plan, then that would mean he wasn't all knowing or all perfect. Since a change in the original plan means the original plan was imperfect.
It is an oxymoron and a paradox and a fallacy all rolled into one.