Horizontal and vertical parity check

[MissP.25_5]

Hello. I need help in detecting error. The question in the attached file is to first fill in the blanks with vertical and horizontal parities. Secondly, it says that there is an error in the circled part. My problem is, how do I find that error and why is there an error? In the second image, I show you that I have answered question no. 1.

 

[UltrafastPED]

You are using even parity checks.

You would normally detect an error in a single bit because the parity check bits are wrong for the corresponding row and column.

From the information that you have provided there is no error; perhaps the problem asked you to _generate_ an error indication for that bit?