emails being blocked

[CRG 0]

I work on a saas application and we use sparkpost to communicate with clients from our product however some of our platform emails are not reaching our users, particularly those using outlook or hotmail. In Sparkpost the bounce report shows the following information:  550-"JunkMail rejected - mta# [a.b.c.d]:55522 is in \n550 an RBL, see Blocked - see http://www.spamcop.net/bl.shtml?a.b.c.d"

I have tried to understand what the issue is but am not very experienced in this domain. Can someone please help or make a recommendation of where I might be able to find help?

Thanks in advance for your time.

[Derek T 0]

You have munged the one bit of information we need in order to help: the IP address.

What did it say when you followed the unmunged link?

Edited January 20 by Derek T

[cooper02 0]

We are having almost the same issue. Any update here?

[Lking 0]

As Derek T said, without an IP address it is not possible for anyone here to provide any additionally information or advice.

Did your system return to you a link to SpamCop?  What information was provided when you followed the link?