Email is not being sent to the vendor

Dear All,

I am facing a concern where the Purchase order output email is not triggering to the vendor. When I have checked in the SPPFP transaction code, I am having the below error.

I have checked the below and all are seems to be fine.

1.) In the BP transaction code, the vendor email id and communication method has been maintained correctly.

2.) The table entries - BUT000, BUT020, ADR6, ADRC have been checked and the data is available in the tables.

Could you please advise whether you have any suggestions on this. Thanks in advance for your help.

Best Regards,

Bharathi