I study in north Cyprus and I bought a refundable return ticket when coming here from Nigeria but I'm not going to be needing it because I won't be coming home at that date. Someone back home is supposed to collect the refund but the Turkish airline back in Nigeria said they'll need authorization. Please how do I go about it and do I need to present my residency permit or any other document? Do I go to Turkish Airways at the airport or any other office?
I flew with them few times & need to cancel my trip to London. Had no problem in refund process (But i bought from sales office indeed and currently live in Istanbul so its very close to me :) )
If you bought an online ticket you can cancel it through their website
http://www4.thy.com/customercontact/Start.tkf (Thats their customer form)
Otherwise if you bought it via a sales office or credit card you should contact related sales office bro.
But all tickets rules can vary so better contact them both ways or you can write their Facebook Page. Here's whole their contact info. Sales offices & phone numbers..etc.. Hope it helps.