If you need to fix settings for Meeting ID field in Meeting Attendance object:

1. Click the Setup gear (upper right) and select Setup

2. Click the Object Manager tab and select the Meeting Attendance object from the list in the central panel

3. Click Fields and Relationships on the upper left

4. For the Meeting ID row, click the down-arrow on the far right to drop down a menu and select Delete

5. In the popup, click the blue Delete button to confirm

6. Do Steps 78-82 but just click Save instead of Save & New at the end

7. Re-grade by using the App Launcher to open the Grader App and follow instructions to run the scoring routine again and then be sure to reload the page to see the updated error list & grade certificate