For a while I was not getting the padlock symbol, but then followed your documentation and used System>Global Config>Server>Force HTTPS and Admin Tools>SEO and Link Tools>Convert all links to HTTPS when site is accessed over SSL.>Yes
That appears to have done the job. However, when I use www.whynopadlock.com to check my site I see a warning that:
"You currently have TLSv1 enabled.
This version of TLS is being phased out. This warning won't break your padlock, however if you run an eCommerce site, PCI requirements state that TLSv1 must be disabled by June 30, 2018. "
I have tried to find more information on this, in particular where in Joomla or Admin Tools I can make the necessary correction. I wonder if you might be able to advise so that I can fix this before the deadline.