Just to be clear... my situation was with a new switch ( TL-SG1024DE)... not after updating the firmware. The installed firmware was up to date on my new switch... but still required the reset.

System reset fixed my 802.1Q VLAN too... Default_VLAN was not visible before reset as Davidj2 said...

Hello.... just wanted to let the group know I'm experiencing the same issue on a new TL-SG1024DE An answer to this question would be much appreciated. Thanks, Joe