@Lunala 

Hi,

Did you set up a password when you first installed the NX510v or is this the first time you are trying to log into the NX510v ?

In case it was the former and you can't remember the password you chose, then the only way to get back into NX510v is by resetting it.

However, if you never set a password on your own, then the password must have been set by the ISP who gave you the NX510v. If that was the case, then first check if the device password might be printed on a label that is usually attached to the backside or the bottom of the device. If there is no password printed on the NX510v, then your only option to get the password would be to contact the ISP who supplied the NX510v and ask them what the password is.