Everything I tested comes out as expected. I also have no idea why it works for different lengths, but not for the same lengths, even when using the same method (slightly adjusted ofc so the counters i en j increase for same length). Won't validate when checked seperately either. I even added the checks for ASCII and to see if the string is empty, yet even the empty check won't validate (even when I added the first == null to the checks too). That's not exactly a rocketScience coding anymore at this point. What is going on here???