Turkish Airlines Ticketing And Customer Service Issues

I bought a ticket with Turkish Airlines for my elderly mother to fly to Antalya on 11 Sep to fly on Oct 16. A week before her flight I contacted the arilines to ask for a wheelchair assistance for my mother and got a confirmation that a request was approved, etc. When my Mother showed at the airport at the middle of the night, she learned that there was no ticket and money was refunded. There was no email or phone call in advance informing me about it. Since then we've been trying to get a simple answer. Why and who canceled the ticket???? After numerous emails back and forth they respond that they can't issue a refund. And we are not seeking a refund, we are seeking an answer to our simple question.