Avast account won't stay logged in between PC start-ups

Whenever I switch on my PC and start Avast Secure Browser I have to log into my Avast account (sync is paused) and I am asked to ‘verify that it’s you’ and ‘sign in again’. I cannot find any way of avoiding this happening. I do remain logged in if I close and reopen the browser without powering off the PC. Is there a flag or setting I’m missing?