Same issue in Muscat.
Officially however, it is Turk Air.
I'm not allowed within a donkey's roar of a radar console, but for my advice is to just roll with it, as long as it doesn't affect things too much.
"ICAO DOC 8585 states that the radio telephony callsign for Turkish Airline is
"TURKAIR""
....you wouldn't happen to be German, would you?
"Zat ist not vat it zays in de manual!"
