I'm trying to solve some problems with the Wolfram Problem Generator. After clearing some problems, I got into the question on the screenshot. The answer is correct, the normal Wolfram Alpha also says so, but the Wolfram Problem Generator is not able to parse the correct result? Am I doing something wrong? Is there a better way than writing the matrices code by hand? Because there are only options to create 2x2 and 3x3 matrices.

Would love to get some feedback. I really don't know what I am doing wrong. There also aren't any strange characters there that could stop Wolfram Alpha from parsing it. Thank you for your help.