Dropbox issues, not backing up

what am i doing wrong?

Traceback (most recent call last):
File “/home/frappe/frappe-bench/apps/frappe/frappe/integrations/doctype/dropbox_backup/dropbox_backup.py”, line 44, in take_backups_dropbox
did_not_upload, error_log = backup_to_dropbox()
File “/home/frappe/frappe-bench/apps/frappe/frappe/integrations/doctype/dropbox_backup/dropbox_backup.py”, line 136, in backup_to_dropbox
dropbox_client = get_dropbox_client()
File “/home/frappe/frappe-bench/apps/frappe/frappe/integrations/doctype/dropbox_backup/dropbox_backup.py”, line 166, in get_dropbox_client
token = dropbox_client.create_oauth2_access_token()
File “/home/frappe/frappe-bench/env/local/lib/python2.7/site-packages/dropbox/client.py”, line 189, in create_oauth2_access_token
r = self.rest_client.POST(url, params, headers)
File “/home/frappe/frappe-bench/env/local/lib/python2.7/site-packages/dropbox/rest.py”, line 322, in POST
return cls.IMPL.POST(*n, **kw)
File “/home/frappe/frappe-bench/env/local/lib/python2.7/site-packages/dropbox/rest.py”, line 260, in POST
File “/home/frappe/frappe-bench/env/local/lib/python2.7/site-packages/dropbox/rest.py”, line 235, in request
raise ErrorResponse(r, r.read())
ErrorResponse: [401] u’Access token not found.’

I have not used the dropbox module yet. But, by the looks of the error, you have to re-authenticate your oauth login. “Access token not found” could either mean the token given to you expired or was not found in the database.

Thank you @Felipe_Orellana - but where do i insert the access token? is the encryption_key same as Access token?

I am confused what to do with the access token