Turk Telekom GSM Line Switch Failure

On June 7, 2024, I changed my Turk Telekom line from postpaid to prepaid. Before, I had been using the line without any problems, but after the change, I noticed that I was no longer able to receive or send SMS messages. I had a conversation with customer service about the problem, and although they made an effort to assist, we were unable to reach a resolution. Living abroad has its challenges, especially when it comes to accessing applications like e-government, mobile banking, and other SMS-reliant services. This situation has really upset me. I would like a solution to this problem.