With over 50,000 organisations registered on Do-it, it may be that you're wanting to post opportunities for organisations that already exist on our platform.
Firstly, use our organisation search to confirm if your organisation is already registered with ourselves. If it is, drop an email to firstname.lastname@example.org telling us the organisation you are looking to become administrator for, with a link to the organisation page. We will then advise you on who is currently set up as administrator for that account, and advise on the best steps for being able to start being able to manage that organisation yourself. Normally that will involve having you get in touch directly with current administrators, as we find it tends to avoid confusion in the long run if all current administrators for an organisation are aware who each other are.