a27-115.smtp-out.us-west-2.amazonses.com (54.240.27.115) failing SPF and DKIM checks and listed in SpamCop RBL

Recently, I started getting DMARC emails stating the 54.240.27.115 (a27-115.smtp-out.us-west-2.amazonses.com) is failing SPF and DKIM checks for my domain (from spamexperts-02.hostns.io, if this helps).

X-DKIM-Status: none /  / us-west-2.amazonses.com /  /  /
X-DKIM-Status: pass /  / amazonses.com / amazonses.com /  / 

Today, I also got this failure notice from Amazon:

Reporting-MTA: dns; a27-115.smtp-out.us-west-2.amazonses.com

Action: failed
Final-Recipient: rfc822; info@ronitbaras.com
Diagnostic-Code: smtp; 550-"JunkMail rejected - a27-115.smtp-out.us-west-2.amazonses.com
 550-[54.240.27.115]:47579 is in an RBL: Blocked - see
 550 https://www.spamcop.net/bl.shtml?54.240.27.115"
Status: 5.3.0

Seems to me that this server hasn't been added properly and is causing problems.

I've had DMARC failure reports for other servers as well, which makes me suspect an even bigger setup problem, although this particular server seems to be involved more than others, and I see online that others have had issues with it as well.