My recicle bin has disapear. How can i retrieve it?

Do you mean the Trash folder that goes with your email accounts, or the Recycle bin associated with your File Explorer?

The trash folder in email account.

See https://support.mozilla.org/en-US/kb/profiles-tb to locate your profile.

Using your File Explorer, go to your profile and the look at the level below that for Mail, and below that for Local Folders. There should be a file named 'Trash' and another named 'Trash.msf' If either the 'Trash' file or the 'Trash.msf' file is there, delete them (!). Then restart TB. It should recreate the Trash.