Probably has to do with how the variables are passed -- that is a generated template from modify.cgi

The record is read, but when modified the data is probably not passed to the form and back again. You can pass it, and keep track of it fairly easily.

You have to do a look up, then when you find it, you can pass it explicitly to the form. To pass it back, make it a hidden variable "ID" and assign it the value if "ID" then, make sure to read it back if you need it.