follow up on (something)

1. To contact someone again or at a later time to get more information about something. Is the project is still on schedule? Please follow up on this with Ingrid to be sure. The doctor's office never called me back, so I'm going to follow up on that tomorrow. If Victoria doesn't return your call, let me know, and I'll follow up on this. I'm pretty sure she's afraid of me anyway.

2. To check that something was done properly. Ben never follows the instructions I give him, so can you please follow up on his assignment? Don't worry, I'll follow up on this and make sure the alarm is set properly at the end of the day. Can you please follow up on the printer and make sure that repair really fixed everything?