I have to generate 30,000 new certificates for the main domain name every week

I have to process 30,000 different domain names to generate certificates every week,
for example :
www.a.com a.com
www.b.com b.com
www.c.com c.com
.....
Until 30000-50000 integers, one certificate for each domain name, I received a rate limit, I submitted a ticket but did not get help, they may be too busy to see