HTTP 500 Error creating Invoices

I’ve been using a custom written API integration to send invoices to Freeagent for years. It’s always worked fine.
This morning, the calls to Create Invoice stoped working. Only result I get in the HTTP header is this:

HTTP/1.1 500 Internal Server Error
Date: Thu, 13 Jun 2024 09:51:30 GMT
Content-Type: application/json
Transfer-Encoding: chunked
Connection: keep-alive
Server: nginx
Cache-Control: no-store
Pragma: no-cache
X-Request-Id: 1-666ac122-57834f4802207cb2448e1108
X-Rev: cefb506815ed0d726a04a4e228958b1f2e862dbc
X-Host: ip-10-132-213-28
X-Runtime: 0.206036
X-Frame-Options: SAMEORIGIN
X-XSS-Protection: 1; mode=block
Referrer-Policy: strict-origin-when-cross-origin
vary: Origin
Strict-Transport-Security: max-age=31536000
X-Content-Type-Options: nosniff

Payload JSON example is:

{
	"invoice" : 
	{
		"bank_account" : "https://api.freeagent.com/v2/bank_accounts/381770",
		"comments" : "",
		"contact" : "https://api.freeagent.com/v2/contacts/4484381",
		"currency" : "GBP",
		"dated_on" : "2024-6-13",
		"ec_status" : "",
		"invoice_items" : 
		[
			{
				"description" : "13/06/2024\rline 1",
				"price" : "1",
				"quantity" : 1,
				"sales_tax_rate" : 20
			}
		],
		"payment_terms_in_days" : 28,
		"reference" : "GTECH2624"
	}
}

Nothing has changed at my end - is this a Freeagent side issue?

Hi there :wave: James from FreeAgent here.

Thanks for getting in contact.

We noticed some issues earlier and have now deployed a fix. The timeframe of this incident was between 10:33 and 10:57.

We have a Status page https://status.freeagent.com/ for any further updates, this particular incident though has now been marked as resolved.

Please do let us know if you require any further help, we’ll be happy to take a look for you.

Best regards,
James