On interface it works, but returns an unknown and non debuggable error only when testing on the portal url

DO you see any errors in stdout.log or design-errors.csv?

ERROR 2024-05-28T17:32Z Unable to route READ request GROUPS.getCredentials for groups within 20 seconds
INFO 2024-05-28T17:39Z Portal data path configured with prefix of /mnt/portal.
INFO 2024-05-28T17:39Z Invoking the TVM took 3703.0 ms
INFO 2024-05-28T17:40Z Portal data downloaded from S3 in 255.0 ms
INFO 2024-05-28T17:40Z Portal data unzipped in 1.0 ms
INFO 2024-05-28T17:40Z Metrics server ready at http://100.64.159.88:9099/
INFO 2024-05-28T17:40Z Loaded configuration from file in 6 ms
INFO 2024-05-28T17:40Z Loaded configuration from file in 1 ms
INFO 2024-05-28T17:40Z Parsing built-in types from /appian/cdt/generated/generated-pojo-types.xsd
INFO 2024-05-28T17:40Z Parsed 180 datatypes in 79 ms
INFO 2024-05-28T17:40Z Parsing built-in types from /appian/cdt/system-record-types.xsd
INFO 2024-05-28T17:40Z Parsed 2464 datatypes in 127 ms
INFO 2024-05-28T17:40Z Parsing built-in types from /appian/cdt/generated/generated-plugin-pojo-types.xsd
INFO 2024-05-28T17:40Z Parsed 4 datatypes in 0 ms
INFO 2024-05-28T17:40Z Parsed 0 datatypes in 0 ms
INFO 2024-05-28T17:40Z Parsed 3104 datatypes in 226 ms
INFO 2024-05-28T17:40Z Bootstrap environment configured in 377 ms
ERROR 2024-05-28T17:40Z An error occurred while trying to read the security token from "/conf/appian.sec". No security token will be sent when connecting to engines.
INFO 2024-05-28T17:40Z Portals Tracing Enabled: true
INFO 2024-05-28T17:40Z Application context configured in 698 ms
INFO 2024-05-28T17:40Z Loading all objects from connectedsystem directory
INFO 2024-05-28T17:40Z Read import properties from file in 0 ms
INFO 2024-05-28T17:40Z Retrieved import properties in 23 ms
INFO 2024-05-28T17:40Z Loaded 1 objects from connectedsystem directory in 313 ms
INFO 2024-05-28T17:40Z Loading all objects from recordtype directory
INFO 2024-05-28T17:40Z Loaded 0 objects from recordtype directory in 0 ms
INFO 2024-05-28T17:40Z Loading all objects from processmodel directory
INFO 2024-05-28T17:40Z Loaded 0 objects from processmodel directory in 1 ms
INFO 2024-05-28T17:40Z Loading all objects from datastore directory
INFO 2024-05-28T17:40Z Loaded 0 objects from datastore directory in 0 ms
INFO 2024-05-28T17:40Z Loading all objects from translationstring directory
INFO 2024-05-28T17:40Z Loaded 0 objects from translationstring directory in 0 ms
INFO 2024-05-28T17:40Z Loading all objects from translationset directory
INFO 2024-05-28T17:40Z Loaded 0 objects from translationset directory in 0 ms
INFO 2024-05-28T17:40Z Loading all objects from portal directory
INFO 2024-05-28T17:40Z Loaded 1 objects from portal directory in 9 ms
INFO 2024-05-28T17:40Z Loading all objects from connectedsystem directory
INFO 2024-05-28T17:40Z Loaded 1 objects from connectedsystem directory in 9 ms
INFO 2024-05-28T17:40Z Scanned 4308 system rules in 17 ms
ERROR 2024-05-28T17:40Z An error occurred while trying to read the security token from "/conf/appian.sec". No security token will be sent when connecting to engines.
INFO 2024-05-28T17:40Z Loaded 8 rules in 819 ms
INFO 2024-05-28T17:40Z Loaded 0 XSD schemas in 13 ms
INFO 2024-05-28T17:40Z Generated 0 ecore models in 343 ms
INFO 2024-05-28T17:40Z Portal Name:cobranca-entidade-cedente Portal ID:d120e334-19dc-11ef-89ef-666622b700c1 Site ID:78317 Locale: pt
INFO 2024-05-28T17:40Z Minimal evaluation environment configured in 1627 ms
INFO 2024-05-28T17:40Z Serverless evaluation environment configured in 4067 ms
INFO 2024-05-28T17:40Z Loaded configuration from file in 0 ms
INFO 2024-05-28T17:40Z Server ready at http://100.64.159.88:8080/

David J (NTT DATA) 

Could you check permissions of the service account on the obejcts you are using?

Could you check permissions of the service account on the obejcts you are using?