What actually happened was I tried to update my plugins but it said they needed to be registered. The site has been active for several years and registered with toolset. I thought it must be because I migrated the site to a new host recently, and is now accessed on https, not http. I tried the old reg code which failed, created a new one for the https which failed. Manually updated the plugins, deleted the old site reg codes, created a new one which failed.
I suspect that this is due to the "cURL error 60: SSL: no alternative certificate subject name matches target host name 'api.toolset.com'"
We have opened a ticket about this to our systems team for further investigation on the issue.
You can still update your plugins by performing a manual update by downloading the newest versions and uploading them to your site using FTP.