Problems with Corendon Airlines' Excess Baggage and Non-Refundable Fees

I had 8 cabin baggage allowance for my Bremen-Antalya flight on 02.07.2023. I paid 49.99 euros for the ticket and 10 euros for cabin baggage, ie 59.99 euros in total. Since I had cabin baggage, I went directly to the boarding section. In the boarding section, the airport attendant (only me on the whole plane) wanted to weigh my suitcase and first demanded 18.5, 185 euros due to the excess weight. When I showed him that I paid an 8 kg baggage fee, he demanded 105 euros for 10.5 kg. I would like to reiterate that they only want to weigh my luggage on the big plane. Everyone was taken to the plane and I was waiting in the boarding section. They asked if I wanted to pay by card or cash, and I said that I wanted to pay by card. They couldn't find a POS machine, but I said it wasn't my problem. They checked for the device for about 5 minutes, but they could not find it and threatened me that I would not be taken on the plane if I did not pay cash. I reluctantly gave them 150 euros in my wallet. I waited about 5 minutes for the change, but this time they could not find the change. While waiting for the change, I saw that the receipt they prepared for me had been changed from 105 euros to 150 euros. They illegally tampered with a property document and asked me to go to the plane. What was done was completely illegal and they did not give my money back. I paid a 150 euro excess baggage fee for the plane ticket I bought for 59.99 euros. When I returned to Turkey, I reported this situation to the company, especially the call center. While waiting for a refund, the company did not give my money back. As someone who has traveled many times over the years, I have never encountered such a disgraceful situation in my life. I still can't get my money back and I can't find an authorized contact person.