I've set up SpamAssassin on my server
I've configured my dmarc, DKIM and spf records in my domain's DNS which wasn't easy to figure out how to do correctly but for a while after I'd done this the spam stopped but now its back again.
Here's my dmarc, DKIM and SPF records all as TXT records on the DNS (I changed actual values so these don't reflect actual data on my domain).
dmarc:
v=DMARC1; p=quarantine; rua=mailto:email; ruf=mailto:email; aspf=r; adkim=r
DKIM:
v=DKIM1; k=skh; p=MIIBIkug876GKgut785ukutioogiyry47gmhMHFyrJKkmsOyyK+J
spf:
v=spf1 +a +mx +ip4:mail server ip -all
What more can I do to stop the spam?