The JVZoo system, as a whole, actually has 3 different accounts, each with a unique login (unless you change the passwords yourself).
You can find the login page and lost password link for each of these accounts here:
Vendor/Affiliate account (for selling and promoting through the JVZoo system): https://jvzoo.com/auth/login
Customer account (where you can access products you have purchased through JVZoo): https://customer.jvzoo.com/
Support Desk account (in order to submit and view support tickets for JVZoo): https://jvzoo.zendesk.com