One three different hotspot setups i have im getting this message after a few weeks.
I run hotspot and a dhcp server to hand out a private IP. it also uses radius for authentication but that does not affect this.
if i do:
/ip pool used print
I will see maybe 30 used IP address, but my pool is 200.
Even a reboot will not fix it. the only solution i have found is to delete the dhcp server and pool and remake them.
two are running 2.9.40 and one 2.9.38. both rb 133s that run great otherwise
tks