Sophos Splunk App Error

I have configured the Sophos Central Addon for Splunk but its not pulling in any events and I see the following errors in the splunkd log

01-12-2023 17:59:40.417 +0000 ERROR PersistentScript [19838 PersistentScriptIo] - From {/opt/splunk/bin/python3.7 /opt/splunk/etc/apps/TA-sophos-central-addon-for-splunk/bin/TA_sophos_central_addon_for_splunk_rh_settings.py persistent}: solnlib.credentials.CredentialNotExistException: Failed to get password of realm=__REST_CREDENTIAL__#TA-sophos-central-addon-for-splunk#configs/conf-ta_sophos_central_addon_for_splunk_settings, user=proxy.