Disabled as mentioned by Murtaza.Hey @murtaza12 and others, I saw from your screenshots that you're using a Huawei modem - and I, too, see that the default end-user username and password have some settings restricted (for me, it's the ability to change DNS servers).
Have you tried using "telecomadmin" and "admintelecom" as the username and password respectively? Because this works on PTCL's GPON service (and I was successfully able to change my DNS server settings).
Umm, just double checking but is this the newly installed ONT by PTCL? I think they'd disable it too as soon as it establishes connection. I believe this is more or less SOP to disable but then its PTCL so you never know.