"మీకు" = "to You" [formal]; "ఫోన్" = (to) "phone"; "చేస్తున్నాం" = (we) "doing". Meaning, we are phoning you.
"కాల్" = "to phone" can be good, but still lot of old population is not used to it. Moreover "కాలు" means "leg" without "న్".😀