switch 4500x vss telnet access issue

[mahmoud.abdelkhalek]

i have 2 switches 4500x with VSS and i can access with telnet and console
but once i cant access telnet and console and appear password required, but not set

[Reza Sharifi]

Make sure you have "login local" enabled under the vty lines.

also, make sure you have set the username and password

example:

username cisco password cisco

username cisco privilege 15

HTH

[mahmoud.abdelkhalek]

all telnet configuration was exist and after 6 month VSS configuration telnet configuration deleted

[Mark Malone]

shouldn't be using telnet its insecure you can see passwords on a wireshark , use SSH
what happened for it to be deleted ,. was the device rebooted , config not saved ?
we cant tell from the information thats been provided so far , is there any logs form the day the issue occurred ?