How to edit the sidebar form content? I recently inherited this website from a colleague of mine: http://cityrentacar.gr 

It runs under Drupal 7 with the Nexus theme. 

I am trying to edit the fields/select-options on the sidebar request form but as soon as i login i only see a configure button over the form?

Is there a way to manually edit the field?

Any help would be appreciated.

Thanks.
It looks like your predecessor used jotform to set this up, see this screenshot:

If I am right, then you should be able to edit these values via the related jotform account.
Hope this does it for you, it seems you need the get those jotform credentials for the linked jotform account!