I don't know your process or what your role entails but if you're responsible for output then you should be part of the process. We do scrum and my manager join

I don't know your process or what your role entails but if you're responsible for output then you should be part of the process. We do scrum and my manager joins standup every day. Are tickets taking longer than estimated, or are estimates higher than before? Do you estimate as a team? You should be part of the estimation process. If estimation is normal, the you should be finding out the first day that a given ticket is not on track. Get devs to make daily commitments and pay attention to when they are not met. What went wrong? If you wait until the end of the estimated time and then ask why its not done, you will never get accurate answers. You have to track it more frequently than that.