While doing a low frequency search via the command “lf search” on my Elechouse Proxmark3, I encountered the error
#db# Error, unknown function 26
It seems any message prefixed by #db# is a message coming from the proxmark3, rather than the proxmark software running on your computer. This would indicate a bug in the proxmark software!
Solving this bug was relatively simple, just update the firmware!
To do that, check out my guide on proxmark3 firmware updating.