A thumb drive has, perhaps only recently, some means of turn itself readonly for some days as you burn there something - maybe just to preserve its life as a flash memory further.
That unit isn't bricked at all, and you may wish to set the readonly flag to zero earlier...
Please look at hdparm --security-help
from your device.
You may want to run SOME of them if not ALL; try to figure out the correct sequence.
The idea here is to:
hdparm --security-mode m --user-master m --security-freeze device;
hdparm --security-mode m --user-master m --security-set-pass null device;
hdparm --security-mode m --user-master m --security-unlock null device;
hdparm --security-mode m --user-master m --security-disable null device;
hdparm --security-mode m --user-master m --security-erase null device;
hdparm --security-mode m --user-master m --security-erase-enhanced null device;
To fully disable the readonly feature of your device.
I was successful with this on a USB 2.0 64G multilaser (tm) pen drive here in Brazil a month ago.