I Experienced Unexpected Price Hike and System Glitch with Turkish Airlines

Hello,
I was purchasing a direct flight ticket from THY and was about to proceed to the payment section when I noticed a message stating, "Your transfer will be handled by a different company." Curious about what this meant, I went back a step to look for more information. Unable to find any, I proceeded to the payment section again only to receive a message saying there were no available seats, even though I had already selected everything and was ready to complete the payment. I went back to the beginning and saw that there were still seats available at the same time, but the price had increased. Why is the price increased while I'm in the middle of the booking process and being told there are no available seats? I had already selected and proceeded to purchase the ticket. Why are you causing inconvenience to us? If the price is going to increase, at least ask if we want to continue with the new price. Why does the system kick us out saying there are no seats left? Prices can change constantly, but forcing me to cancel my selected and paid-for booking to make me buy it at a higher price is unfair. I will look for tickets from another company. These actions do not suit THY...