Client and I signed a contract that I will create logo, brandbook & web design. Everything was going quite well. I got 50% prepayment and all the tasks were carried out according to a schedule which was an appendix to the contract.
At the end of website design workflow when content structure and design style was chosen, I prepared the mockups for the desktop and for 2 other breakpoints. Again, everything was according to the schedule and it was the end of it. The client was not happy with the result so I made small changes free of charge. After I delivered the corrections I sent the invoice. He was still not happy with the results, refused to approve the work because there was a lack of quality as he said. Obviously, he does not want to pay the invoice. I offered him an additional round of changes but for extra payment. Now he is threatening me with EU Consumer rights that my contract and workflow are not according to the law and he wants changes for free.
From my point of view, he did not take the contract that seriously and now wants to have huge changes after everything is done. What would you do in this situation? Does he have a point that I'm doing something wrong by charging for additional editions?