Looking at the message and your domain name, I don’t see any issues. Your domain name is correctly set up on our end, and has correct A records, SOA records and NS records. Your domain name is fully working, and so our our nameservers, so I’d say that your domain is compliant with that part of ZISPA’s terms.
So I don’t know why ZISPA is complaining about the nameservers.
If ZISPA really doesn’t like our nameservers for some reason, you could also switch to other nameservers, like those from Webzim (if they provide them) or a specialized provider like Cloudflare. You can then point the domain name to our website hosting from those external nameservers:
I will stress that it’s silly to have to jump through these hoops to work around what I can only describe as broken registry checks. But the option exists, if you need it.