Updated Avast won't launch Full Virus Scan

I have just updated my Avast AntiVirus and now cannot launch the Full Virus Scan. It goes instantly to “Done - no problems found” and when I check the can history it has not registered as the scan being launched.

I have been able to run a “Targetted Scan” on my main drives. Is this a change in the latest update, or do I need to repair Avast?

I have program version 19.5.2378 (build 19.5.4444.497) updated 26 May 2019, with Virus definitions updated a couple of hours earlier.

Repair >> https://support.avast.com/en-eu/article/Repair-Antivirus

Reboot when done …