Failing 2 out of 3 hidden cases. Can anyone help?

Question

https://code.sololearn.com/cD4u2ejKnHBh/?ref=app
Any suggestion?

Answer 1

the hour number should have two digits, when it has one digit, add a 0 at the beginning:

01:20
05:15
14:34

Answer 2

10x.
Worked like a charm.