How to fix Nmap telnet-brute.nse: "Invalid usernames iterator" error?

Question

Burglary protection

I'm trying to iterate:

-p 23 --script telnet-brute --script-args userdb=myusers.lst,passdb=mypwds.lst 192.168.0.50 -oN D:\bruted_log.txt

the Telnet password I know to my router using the telnet-brute.nse Nmap crypt.
Returns an error:

Nmap scan report for dlinkap.Dlink (192.168.0.50)
Host is up (0.0061s latency).
PORT   STATE SERVICE
23/tcp open  telnet
|_telnet-brute: Invalid usernames iterator

what is this error?
I suppose the format of the contents of the files mypwds.lst and myusers.lst is not correct
.