Your mentor is only required to schedule sessions and leave feedback on your work during the 4 weeks of the course you are enrolled in. Sometimes mentors will be happy to help you wrap up your work in the week or two after the course, but this is at their individual discretion. Often, they may not be able to offer this due to other commitments.
To avoid encountering this situation, aim to stay on track and get through the bulk of your projects and calls within the 4 weeks of the course. If something’s come up and you think you won’t be able to catch up before the end of the month, you might want to consider postponing your enrollment.
Although access to feedback and mentoring is time-limited, remember that you will always have access to the course curriculum and platform, so if you’ve got projects to finish up, you’re welcome to return any time to work on them.