While using OIC rest adapter to PUT file to OCI bucket, got 503 service unavailable error

Please let me know if you have any suggestion.

Below is the error message:
response from http://rest-adapter:8080/endpoint/outbound/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/request?op=execute is 503 ==> Service Unavailable

From OIC integration we PUT file to OCI object storage using rest adapter. This works fine everyday, but today we got 503 service unavailable error suddenly

Below is the snippet from flow logs where the error occurred:

{
"eventId": "xxxxxxxxxx-xxxx-xxxxxx",
"eventReportingLevel": 10,
"erroraActionType": 8,
"errorType": 17,
"errorCode": "net.http.503",
"errorComponentType": 1,
"errorSummary": "response from http://rest-adapter:8080/endpoint/outbound/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/request?op=execute is 503 ==> Service Unavailable",
"flowEventCreationDate": 1737056113747
"iterationCount": "1-1",
"actionType": 8,
"errorState": 500,
"errorAutoRetriable": false,
"milestone": "Ei0#m",
"errorActionName": "Put_File_OCI",