I'm calling to tell you about my day."
"I'm calling to accept your invitation."
"I'm calling to answer your question."
"I'm calling to book a reservation at your restaurant."
"I'm calling to complain about something."
"I'm calling to thank you."
"I'm calling to support your decision."
"I'm calling to remind you of our dinner plans."
"I'm calling to report a lost wallet."
"I'm calling to receive my prize.