Take a close look at your else block. What will happen with your code if multiple records in a given patient have systolic pressure >=180 and diastolic >=110?

Tests are random, so it's normal an incorrect solution doesn't fail the same amount of tests on each trial.

For the rest, you should follow the track given by kemptosa.

It looks like you may be double counting some patients somehow, I would look at the expected and actual results for each test case.