Sen remittance advice does not send remittances for some suppliers

Hi,

There is ni recent change in server side. We have Oracle Applications : 12.1.3

Below the log of a remittance advice

Loaded email attachment file prefix from DB: Message { Code = IBY_FD_EMAIL_ATT_PRE, Cause = Payment}
Preparing for email delivery
SMTP server host: null
Email subject: s Remittance Advice: Payment Number - 00122
Recipient: a.aaa@aaa.com
Content file name: Payment98284.html
Email send from: aaa@aaaaa.com
before calling XDO req.setDocument()
before calling XDO req.submit()
Request Failed with Status ::12
The delivery request was failed because of the error in the server side.
Sucessfully delivered separate remittance advice/payer notification.
Exit: iby.scheduler.SRAAndPayerNotif.doElectronicProcessing()
There are no payments that require printed separate remittance advice
There are no payments that require printed separate remittance advice
Delivery Method for1 payments is Email
Email is not Provided for 0 payments
Remittance Advice for 0 payments have been sent