You can only issue a Reset Command with the DS1682 once. When you issue a Reset Command, the device becomes read-only forever. The DS1682 was originally designed this way to prevent tampering once an alarm was set for the warranty applications.
We developed a sister device, the DS1683, with the same pinout and the ability to password-protect the memory instead of a one-time Write Protect and lockout forever function. With the DS1683, you can reset and write to the ETC and Event Counter registers without fear of lockout (unless you forget your password).