Payments exist in CiviCRM but not SagePay

[chaplincircle]

3.19
CiviCRM 5.58.1
PHP version 7.4.33
WordPress 6.2.2

We've got 2 (cancelled) payments that look normal in CiviCRM.
There's no trace of them SagePay.
SagePay have said
"For these transactions, we received a response of "body='', statusCode=200, statusMessage='OK' " this is incorrect. An example of correct response seen in other transactions is body='Status=OK\r\nRedirectUrl=https://redactedurl/civicrm/payment/ipn/85725/4/\r\n\".

This is step 4b of the transaction process. https://developer-eu.elavon.com/docs/opayo-server/taking-payments/step-4-you-confirm-transaction#4b

These transactions will have authorization on the customers card but these transactions were not sent for settlement due to the aforementioned error."

Any idea if this is a bug, or just the way the customers were using the site eg leaving a page open too long or even some network issue?

Should also add the configAndLog has
Apr 14 11:44:15 [info] Contribution nnnnn updated successfully
Apr 14 16:46:32 [info] Contribution nnnnn updated successfully
for the 2 payments.

[eileenmcnaughton]

@pradpnayak you have been involved in SagePay most recently - do you have any insight?