We have an Update Object rule for mail eater but whenever an email is processed, it seems like it is trying to create a new Request instead with the following error on the stdlog:
<Date/time> <Server name> spelsrvr 4380 ERROR cr_chg_text_api.spl 1396 AHD58009:Could not create Request. Reason: INVALID - AHD03075:Required attribute type is missing from object Request Activity Log
Creating a new ticket works fine.
This looks to be like this Knowledge Document, but patch ITSM 17.1 and the data loads have been done.
https://comm.support.ca.com/kb/unable-to-save-a-request-ticket-in-ca-sdm/kb000092714