Please open a ticket at Jolla customer support ( https://jolla.zendesk.com/hc/en-us/requests/new ).
Describe in detail what you did and what happened. If you have some “evidence” like screenshots or logs, attach them, too.
How did the issue with the short security code go? Were you connected to C2 with a USB keyboard initially when setting up the code for the first time? Did you set the code in the numeric or alphanumeric mode (of Sailfish)?