Many Moons ago a directive was issued by Airbus expressly forbidding the setting the park brake inflight. This followed an incident when an aircraft landed and the brake was still set
This has potential to wreck the noseleg due to the rapid derotation of the aircraft (cos the mains aren't turning...)
I don't know if the handle was in the "SET" position - but the parking brakes were! If it was a software issue, it's probably been sorted by now.
Safest bet is don't touch the PB handle in flight.
A4