Not so much a bug as a problem
I just solved a puzzle that had 2 8pm slots. I had the correct answer, but the system would not accept it at first. I had to reverse my 2 8pm answers so that the system knew which was which. If there are going to be 2 of the same in any fields, such as the time, the clues need to differentiate which one is being referred to. Or, the answer grid needs to be programmed to accept both possible answers.