If you buyed a Enterprise-Version in 2016 then you should get updates till dez 2018.
If this is the case then you should have got an email with downloadlink. Check you spamfolder; maybe it is there.
If you just buyed the normal Version then you only get updates for 2 Months. In this case your updateperiod is over and you need to buy a new Licence to get updates/newest version.
if you think you should have get an email but you dont: contact support@basic4ppc.com