The manager who gave you a second chance after a bad first month is someone to make proud.

A second chance costs somebody something. Keeping an employee who started badly means your manager absorbed the risk, defended it to whoever asked, and bet on a version of you that did not exist yet, which is a different thing from being nice to you. That bet is still open. The only way it pays out is through what you do next.

Find out what that person actually needs from your role and get good at that specific thing. Tell them plainly that you know what they did. Then be the one who is reliable on the bad nights, because that is what makes the bet look smart.