Why aren't tickets getting created, even after adding the support email address in Freshservice?

Only after the forwarding rule is set up in your support mailbox, would emails come into your freshservice Account as Tickets. So, please make sure that the forwarding is configured from the mailbox of your support email address to the Forwarding Email Address, available under Admin-->Channels-->Email Settings-->and check the "Forwarded To" section corresponding to your email address.

This forwarding rule is for internal operation only and the Forwarded To address would not be displayed to the customer at any point