Unable to print to HP printer using "hp" backend

Issue

We have added a printer using:

lpadmin -p hpprinter -v hp:/net/HP_LaserJet_400_M401dn?ip=10.1.2.3 -m /lsb/usr/HP/hp-laserjet_400_m401dne-ps.ppd.gz -E

however, print jobs submitted are stuck in the queue and do not print. The lpstat command indicates that the job is printing:

# lpstat -p
printer hpprinter now printing hpprinter-6.  enabled since Fri Oct 15 09:54:28 2021

but nothing is actually printed.