The parameters submitted by the interface are different from the parameters returned by the interface

[tianfengLiang]

Recently, I have encountered some inconsistencies in the data returned by your API. I would appreciate it if you could help confirm and investigate the issue.

Here are the details:
We submitted VAT return data through the following API:
https://api.service.hmrc.gov.uk/organisations/vat/{vrn}/returns
The submitted data was:

{
"periodKey": "24B2",
"vatDueSales": 641.15,
"vatDueAcquisitions": 0,
"totalVatDue": 641.15,
"vatReclaimedCurrPeriod": 4780.62,
"netVatDue": 4139.47,
"totalValueSalesExVAT": 63246,
"totalValuePurchasesExVAT": 23903,
"totalValueGoodsSuppliedExVAT": 0,
"totalAcquisitionsExVAT": 0,
"finalised": true
}

The submission was successful. However, when we retrieved the VAT return details using the following API:
https://api.service.hmrc.gov.uk/organisations/vat/{vrn}/returns/24B2

We noticed the following inconsistency:
{
"periodKey": "24B2",
"vatDueSales": 641.15,
"vatDueAcquisitions": 0,
"totalVatDue": 641.15,
"vatReclaimedCurrPeriod": 1092.64,
"netVatDue": 451.49,
"totalValueSalesExVAT": 63246,
"totalValuePurchasesExVAT": 23903,
"totalValueGoodsSuppliedExVAT": 0,
"totalAcquisitionsExVAT": 0
}

As you can see, the values for vatReclaimedCurrPeriod and netVatDue are inconsistent .Why was the data changed after submission?
this vrn number is same.

Could you please help verify this discrepancy and provide clarification? Thank you for your assistance

[tianfengLiang]

Has anyone else encountered similar issues and knows the reason?

[charles-f]

@tianfengLiang

the only time I've ever experienced that - is a customer submits their return as you state in the POST request. Which returned a 201 successful response.

Then the user makes a amendment directly with HMRC - which isn't through an API, process is entirely manual - and then HMRC changes the submitted record their side.

So the GET request then returns the different numbers.

I asked the customer by any chance had they amended the return directly with HMRC and they confirmed they had.

This is a problem because if you cannot amend a submission via the API - you then have discrepancies between what is submitted and what is on their Returns API endpoint.