I don't have any debug info for your site so I cannot see which plugin versions you are using.
If you have the current version of Toolset Blocks (1.1.1) then you should see a Toolset section within the Block editor that offers all of the blocks offered by Toolset (see screenshots).
If you are seeing something different and have the latest plugin versions installed, please let me know.
Hi Nigel. I have 1.1.1 installed. Yes, your screenshot shows the exact place where I have only three blokcs while you have many more. So yes, I see something different and have the latest plugin version installed.
Could you quickly check if there is any conflict from other plugins or your theme?
Disable all plugins except Blocks and switch theme to twentynineteen.
Do you still see the same problem?
If so I'd better take a look at your site if that's okay. I may need to take a copy for testing.
Let me mark your next reply as private so that I can get log-in credentials from you—you may want to create a temporary admin user for me to use that you can later delete. And be sure to have a current backup of your site.