There are a few reasons listed below for this:
-Your account gets disabled if you have more than 5% hard bounce rate and you will get an email regarding the same.
-Our spam filters might have detected that your account is sending some phishing emails and you will get an email regarding the same.
-Our spam filter could also have detected that warmup plan given by Pepipost is not being followed and promotional/marketing emails are sent by you on large scale. Same will be conveyed to you over the email.
-If these are not the reasons of your problem, you need to contact the compliance team on email@example.com .