Unable to upload addon

What does this mean: “Multiple add-ons violating our policies have been submitted from your location. The IP address has been blocked.”?
[I am self hosting the addon on my site, not on AMO]

If you haven’t already, please email amo-admins AT mozilla DOT com for help. This is due to IP address restrictions to protect AMO from spamming. You can also just try submitting from a different location.

Always happy to email amo-admins - but other than ‘try a new location’ (which doesn’t work), I’m just being ignored with no help.