When input field was focused and then blured, we received NaN value in input field.
When user entered 0 value in HH input field and then unfocused the input field, the value changed to 'HH'. User is now allowed to have 0 value in HH input field.
If HH input field has no value and user is entering some number in MM input field, HH input field will be set to value 0. The same will happen if user enter any number in HH field, MM input field will be set to value 0 if there's no value in MM input field.
When input field was focused and then blured, we received NaN value in input field. When user entered 0 value in HH input field and then unfocused the input field, the value changed to 'HH'. User is now allowed to have 0 value in HH input field.
If HH input field has no value and user is entering some number in MM input field, HH input field will be set to value 0. The same will happen if user enter any number in HH field, MM input field will be set to value 0 if there's no value in MM input field.