I'm converting 2019 catalog to 2021 and reciving conversion failure error. I ran the repair several times using 2019 all return succesfully completed. The conversion log file alsways ends withe same message. "An error was encountered in the sqlite database: no such table: face_data_table" My environment has been upgraded from 2015 to 2019 to 2021. All three are on my Windows 10 workstation. My catalog contains 55,095 media items. So it's quite large.
Make sure that there are no missing files in your old catalog. Use the Find>All Missing Files command. If you find any missing files, either relink them or delete them from the catalog. Although this doesn't appear to be related to the error message you are receiving, it wouldn't hurt to give this a try.
Otherwise, I think this is a catalog corruption problem that may need the help of Adobe Support. You can start a chat session by clicking on the blue Contact Us button under the Support menu at Adobe.com.