Here's a breakdown:
* porque: means "why" or "because"
* no hables: means "don't speak"
* con migo: means "with me"
* hoy: means "today"
* senora: means "madam" or "Mrs."
The phrase is missing the conjugation of the verb "hablar" (to speak). It should be "por qué no hablas con migo hoy, señora?"
The corrected phrase in English would be:
"Why don't you speak to me today, Mrs. [Last Name]?"
This phrase is a polite way to ask someone why they haven't spoken to you.