Sync issue

Hi. I have an issue to sync my account as I have already registered before I formatted my computer. Now I had reinstalled firefox and I pressed I have an account and it shows something related to pair a device, but currently the only sync I made is on this computer which I formatted and none other devices sync to the account. I have tried the I don't have the device with me and it shows another page which request for account and password. I had the account and password, but it need the recovery key as well to proceed. What can I do to sync without pairing another device or how can I get the recovery key to proceed sync my stuff which uploaded to the firefox server.

Please do help with me on this issue. Thank You