lost quickbooks licence

Hello community. I have been a long term user of quickbooks pro in the UK latterly using 2018 pro.  However after a recent disaster with a desktop we lost 2018 and its licence and we do not seem to have any way of recovering it.  We still have our 2012 licence from which we upgraded to 2018 (via a 2015 interim step).  Does anyone have any ideas as to how the licence can be recovered (quickbooks telephone support have been no help) or is there any availability to buy 2018 again?

Help!!