For bank transactions the duplication checker works by checking for existing transactions where three things match:
- Date (time isn’t taken into account)
If these three match then it’s considered to be a duplicate. However, if in the same upload you have 2 matching transactions (e.g. in the same statement upload) then it’s not considered as it’s from the same source.
With the API the same would apply. However, I will need to double check, but given each API request is executed as it’s received they would all be different sources as they’re received and executed as they arrive.
Turning the duplicate checker off should resolves this, but please let us know if you’re seeing different.