If the linkset is not mated to the linkset specified by the matelsn parameter, then the action=delete parameter cannot be specified.
Recovery
Display the linkset information. Enter the rtrv-ls command.
Mated linkset information is shown in the MATELSN field.
Re-enter the chg-ls command that generated this error message, specifying a valid combination of parameters. Refer to the command description in Commands User's Guide and to the Database Administration - SS7 User's Guide (SS7 linksets) and to the Database Administration - IP7 User's Guide (IP linksets) for assistance.