Email being relay very slow

Tarun Arora

New Member
How can we figure out if the ESP's API is the cause of issue or MailWizz or Infra.

One fine day i was able to send 44000 emails in 20mins thats like 2000 Emails /Min

But post that its like 44000 Emails in 2hr 20mins average time thats like 400emails / Min

ESP(Pepipost) says its Application issue as we are processing it on time.

Microsoft Azure team says Bandwidth and Infra is adequate.

Please suggest the way out.