Spanish phrase
Llamo por ~.
Meaning
I am calling regarding ___.
When to use it
States the caller's reason for calling. Often used to raise a particular matter such as a meeting or an issue in polite business phone conversations.
Example dialogue
Llamo por la reunión de mañana.
I am calling regarding tomorrow's meeting.
Gracias, voy a consultar la agenda y le confirmo.
Thank you, I will check the schedule and confirm with you.