The easiest way to fix this is to go to the “Organisations” tab at the top, find the organisation you do belong to, click the arrow next to the blue View button, and click “Request membership”.
It may take some time for your request to be processed; when it is done, you will receive an e-mail with a new registration code.
If you are struggling with this, send me a private message with the desired organisation and I can do it on your behalf.