Catalina - touchbar WHITEOUT since update instal

Installed Catalina a month or so ago and after restart touch bar white out fully.

Thought - typical apple software upgrade issue, but unable to find fix online.

Awaited updated version (available 27 sept 2020); now installed and running: Catalina 10.15.7 (19H2)

On: MacBook Pro (13-inch, 2016, Four Thunderbolt 3 Ports)

2.9 GHz Dual-Core Intel Core i5, 8GB

Still touchbar white out. I'm sure i'll be directed to hardwear issue, but some buttons still work and co-incidence with update too clear. There must be a fix please... I'd have thought installing update would solve it...